Beta-Sitosterol (Plant Sterol · 5α-Reductase Inhibitor)

PURPOSE: This research aimed to investigate the protective role as well as molecular mechanisms of Rehmanniae Radix Praeparata and its bioactive compound β-sitosterol in preventing CIHL. METHODS: Network pharmacology and bioinformatic analyses were used to identify the pharmacologically active constituents of Rehmanniae Radix Praeparata and predict their potential molecular targets. The influence of β-sitosterol on hair cell damage, apoptosis, reactive oxygen species (ROS) levels, and target protein expression were evaluated in vitro as well as in vivo. RESULTS: The primary active constituents of Rehmanniae Radix Praeparata were β-sitosterol and stigmasterol. They shared 50 potential targets with CIHL, with MAPK3, SRC, and ESR1 as the top three. Molecular docking combined with dynamics simulations demonstrated strong binding and stable complex formation between β-sitosterol and MAPK3. In vitro, β-sitosterol mitigated cisplatin-induced hair cell death, reduced ROS levels, and restored phosphorylated MAPK3. In vivo, it enhanced hearing, decreased hair cell loss, and partially restored phosphorylated MAPK3 in the cochleae of cisplatin-treat

This systematic review assessed the potential effectiveness and safety of Serenoa repens (saw palmetto) for benign prostatic disorders, mainly benign prostatic hyperplasia and associated lower urinary tract symptoms. Following PRISMA guidance (PROSPERO: CRD420251032255), we searched PubMed, Cochrane and ScienceDirect for human studies from January 2020 to May 2025. Sixteen studies (>3000 participants) met criteria, including randomized trials, observational cohorts, a post hoc analysis, an open-label comparative study and a pharmacovigilance analysis. Overall, S. repens was associated with improvements in symptom severity (International Prostate Symptom Score) in several trials, with variable effects on urinary flow, post-void residual volume, and patient-reported quality of life. Signals of benefit appeared more consistently with hexanic lipidosterolic extracts and β-sitosterol-enriched preparations, and some real-world and head-to-head comparisons suggested outcomes comparable to alpha-blockers with fewer adverse events. Combination therapy, especially with the addition of alpha-blockers, showed larger symptom reductions in select populations, particularly with more pronounced baseline symptoms or prostatic inflammation. However, heterogeneity in extract formulations, dosing, study design, and outcome reporting limited cross-study comparability. Safety findings were generally favourable, with mostly mild gastrointestinal events and fewer sexual adverse effects than reported for conventional pharmacotherapies. Taken together, recent evidence supports S. repens as a potentially useful, well-tolerated option for benign prostatic hyperplasia-related symptoms - especially in certain formulations and as part of combination strategies -

Studies suggest that vegetarians and Asians have lower mortality rates from prostate cancer compared to men who follow a Western diet. β-sitosterol, a key compound of plant-based diets, has been found to induce significant changes in the ultrasonic structure of the prostatic adenomas, making it a promising candidate for further prostate cancer research. Consequently, we investigated the potential of β-sitosterol and the synthetic derivative 2 as potent inhibitors of androgen synthesis, a critical process for the growth and survival of prostate tumor LNCaP cells. Solubilized LNCaP microsomes were used as a source of SRD5A1 and AKR1C3 to monitor androgen synthesis from labeled androstenedione, both in the presence and absence of β-sitosterol or 2. Furthermore, the effect of these steroids on LNCaP viability was determined using the MTT method. Our findings revealed significant insights into the androgen synthesis pathways in LNCaP cells. The most efficient metabolic route for dihydrotestosterone formation was the conversion of androstenedione to 5α-androstanedione rather than from testosterone in LNCaP. This conclusion is supported by the Vmax values for 5α-androstanedione formation (271.05 ± 5.0 ng/mg protein/min) and the Vmax of testosterone formation (80.1 ± 8.0 ng/mg protein/min). Both β-sitosterol and 2 demonstrated substantial inhibitory effects of these enzymes for dihydrotestosterone formation and significantly reduced cell viability, highlighting their therapeutic potential. These findings enhance our understanding of the inhibitory effects of β-sitosterol and 2 on LNCaP cells and suggest their promising application in the

Steroidal 5α-reductase type 2 (S5αR2) is a key enzyme involved in the conversion of testosterone (TST) to dihydrotestosterone (DHT), a crucial process in the development of benign prostatic hyperplasia (BPH). Phytosterols (PSs), natural plant-derived compounds, have been proposed as potential inhibitors of S5αR2, but studies on their efficacy are limited. This study evaluates the inhibitory effects of three PSs (β-sitosterol, stigmasterol, and campesterol) on S5αR2 activity using a combined in vitro and in silico approach. The inhibitory activity of the respective PSs was assessed in vitro, by measuring TST and DHT, while molecular docking and dynamics explored PS interactions with S5αR2's active site. The in vitro tests indicated significantly higher IC50 values (β-sitosterol, 3.24 ± 0.32 µM; stigmasterol, 31.89 ± 4.26 µM; and campesterol, 15.75 ± 5.56 µM) for PSs compared to dutasteride (4.88 × 10-3 ± 0.33 µM), suggesting a lower efficiency in inhibiting S5αR2. The in silico studies confirmed these observations, explained by the lower binding affinity identified for PSs to the enzyme's active site in the molecular

ETHNOPHARMACOLOGICAL RELEVANCE: Benign prostatic hyperplasia (BPH), characterized by prostate enlargement due to cell proliferation, is a common urinary disorder in men over 50, manifesting as lower urinary tract symptoms (LUTS). Currently, several therapeutic options are accessible for treating BPH, including medication therapy, surgery and watchful waiting. Conventional drugs such as finasteride and dutasteride are used as 5α-reductase inhibitors for the treatment of BPH. However long-term use of these drugs is restricted due to their unpleasant side effects. Despite the range of available medical therapies, the effective treatment against BPH is still inadequate. Certain therapeutic plants and their phytochemicals have the aforementioned goals and work by regulating this enzyme. AIM OF THE STUDY: This review aims to provide a comprehensive insight to advancements in diagnosis of BPH, modern treatment methods and the significance of ethnobotanically relevant medicinal plants as alternative therapeutics for managing BPH. MATERIAL AND METHODS: A thorough and systematic literature search was performed using electronic databases and search engines suc

PURPOSE: Androgenetic alopecia (AGA) is the most common type of hair loss in humans, affecting self-esteem and emotional well-being. This study aimed to assess the safety and efficacy of VISPOTM, a standardized saw palmetto oil (2-3% β-sitosterol), in subjects with mild-to-moderate AGA. METHODS: In a double-blind, placebo-controlled, four-arm clinical study, 80 healthy male and female subjects aged 18-50 years were randomly allocated (1:1:1:1) to receive either 400 mg capsules of VISPO or 5 mL of a topical formulation containing 20% VISPO or the respective placebo once daily for 16 weeks. The primary endpoints included hair count (hair comb and hair pull tests) and the self-assessment of perceived efficacy. Objective evaluation was performed using the global photographic assessment score. Hair density, thickness, and anagen/telogen ratio were evaluated using phototrichogram analysis. RESULTS: At the end of the study, oral and topical formulations of VISPO reduced hair fall by up to 29% (p<0.001) and 22.19% (p<0.01) from the baseline, respectively. Hair density increased by 5.17% and 7.61% in the oral and topical VISPO groups, respectively (p<0.001). In addition, oral ingestion of VISPO resulted in a marked reduction in serum dihydrotestosterone (DHT) levels in the subjects compared to placebo (p<0.001). However, the effect of the VISPO formulati

Lower urinary tract symptoms from benign prostatic hyperplasia affect 25% of U.S. men, nearly one-half of whom have at least moderate symptoms. Sedentary lifestyle, hypertension, and diabetes mellitus increase risk of symptoms. Evaluation is focused on determining severity of symptoms and therapy to improve symptoms. Rectal examination has limited accuracy in evaluating prostate size. Transrectal ultrasonography is preferred to verify size when starting 5-alpha reductase therapy or considering surgery. Serum prostate-specific antigen testing is not recommended in routine evaluation of lower urinary tract symptoms, and shared decision-making should be used for cancer screening decisions. The International Prostate Symptom Score is the best way to track symptoms. Self-management methods, including limiting evening fluid intake, reducing caffeine and alcohol intake, toilet and bladder training, pelvic floor exercises, and mindfulness techniques, can improve symptoms. Although saw palmetto is not effective, the herbal treatments Pygeum africanum and beta-sitosterol may be effective. Primary medical treatment involves alpha blockers or phosphodiesterase-5 inhibitors. Alpha blockers offer rapid benefit and can be used for acute urinary retention. Combining alpha blockers and phosphodiesterase-5 inhibitors is not beneficial. For uncontrolled symptoms, 5-alpha reductase inhibitors should be started if the prostate volume is 30 mL or greater by ultrasonography. 5-Alpha reductase inhibitors take up to one year to be fully beneficial and are more effective when taken with alpha blockers. Only 1% of patients with lower urinary tract symptoms require surgery. Although transurethral resection of the prostate improves symptoms, many less invasive options with varying effectiveness can be considered.

The use of synthetic medication for treating alopecia is restricted because of systemic exposure and related negative effects. Beta-sitosterol (β-ST), a natural chemical, has lately been studied for its potential to promote hair development. The cubosomes with dissolving microneedles (CUBs-MND) created in this study may be a useful starting point for the creation of a sophisticated dermal delivery system for β-ST. Cubosomes (CUBs) were prepared by the emulsification method, using glyceryl monooleate (GMO) as a lipid polymer. CUBs were loaded with dissolving microneedles (MND) fabricated with HA and a PVP-K90 matrix. An ex vivo skin permeation study and an in vivo hair growth efficacy test of β-ST were performed with both CUB and CUB-MND. The average particle size of the CUBs was determined to be 173.67 ± 0.52 nm, with a low polydispersity index (0.3) and a high zeta potential value that prevents the aggregate formation of dispersed particles. When compared to CUBs alone, CUBs-MND displayed higher permeating levels of β-ST at all-time points. In the animals from the CUB-MND group, significant hair development was observed. According to the results of the current investigati

Plant-derived 5 α-reductase inhibitors, such as β-sitosterol and phytosterol glycosides, have been used to treat androgenic alopecia, but their oral absolute bioavailability is poor. This study aimed to develop a transdermal drug delivery system of β-sitosterol (BS) using a nanostructured lipid carrier (NLC) incorporated into polymeric microneedles (MN). Using a high-speed homogenization method, NLC was formulated variables were optimized by Box-Behnken statistical design. The optimized formulation of BS-loaded NLCs was incorporated into the chitosan-based MNs to prepare NLC-loaded polymeric MNs (NLC-MNs) and evaluated using testosterone induced alopecia rats. The cumulative amount of β-sitosterol associated with NLC- MN which penetrated the rat skin in-vitro was 3612.27 ± 120.81 μg/cm2, while from the NLC preparation was 2402.35 ± 162.5 μg/cm2. The steady state flux (Jss) of NLC-MN was significantly higher than that of the optimized NLC formulation (P < 0.05). Anagen/telogen ratio was significantly affected by NLC and NLC-MN, which was 2.22 ± 0.34, 1.24 ± 0.18 respectively compared to 0.26 ± 0.08 for animal group treated with testosterone. The reversal of androgen-i

The application of the seed oil of Prunus mira Koehne (Tibetan name ཁམབུ།), a plant belonging to the Rosaceae family, for the treatment of alopecia has been recorded in Jingzhu Materia Medica (ཤེལ་གོང་ཤེལ་ཕྲེང་།) (the classic of Tibetan medicine) and Dictionary of Chinese Ethnic Medicine. This study aims to reveal the effective components and mechanism of hair growth promotion in the kernel of Prunus mira Koehne. Network pharmacology was used to predict the mechanism of action and effective components in the treatment of the kernel of Prunus mira Koehne. The contents of amygdalin in 12 batches of the kernel of Prunus mira Koehne were determined by HPLC. An animal model of the depilation of KM mice induced by sodium sulfide was created, and five effective components that promoted hair growth were initially screened. In the study of the effectiveness and mechanism of action, KM and C57BL/6 mice are selected as experimental objects, three screening tests for active components of the kernel of P. mira are performed, and three effective components are screened out from the eight components. HE staining was used to detect the number of hair follicles and the thickness of the dermis. RT-PCR and immunohistochemistry were used to evaluate the influence of the expression of indicators in the Wnt/β-catenin signaling pathway in skin, including β-catenin, GSK-3β, and mRNA and protein expression levels of Cyclin D 1 and LEF 1. The network pharmacology study showed 12 signaling pathways involving 25 targets in the treatment of alopecia by the kernel of Prunus mira Koehne. vitamin E (3.125 mg/cm2/d), β-sitosterol (0.061

Androgenic alopecia is caused due to genetic disorders associated with the excess level of androgens. The progressive miniaturization of the hair follicles leads the terminal hair to vellus transformation. Dihydrotestosterone, an endogenous sex-linked hormone responsible for the growth of facial hair in males is derived from testosterone circulating in the blood by the action of 5α-reductase isoenzymes. The 5α-reductase1 is found in secretory regions of skin encompassing sebaceous glands and hair follicles. In silico screening of phytochemical inhibitors of 5α-reductase1 identified potential candidates for androgenic alopecia treatment. Further, the molecular docking simulation-based virtual screening of 110 phytochemicals was performed against human 5α-reductase1 to identify the potential lead molecules. The ADMET studies for the lead compounds were undertaken and the results showed that β-sitosterol, brassicasterol, and campesterol could be potential inhibitors of 5α-reductase1. Molecular dynamics simulations of protein-lead molecule complex revealed that, β-sitosterol and brassicasterol complex showed better stability with RMSD similar to raw protein. These compounds could be used as lead molecules in drug development for androgenic alopecia.

BACKGROUND: A wide range of environmental factors, such as diseases, nutritional deficiencies, ageing, hormonal imbalances, stress, and ultraviolet (UV) radiation, may affect the structure and function of the skin that covers the entire surface of the human body. In this study, we investigated roles of red ginseng oil (RGO) in enhancing skin functions, including hair growth and skin protection, using mouse models. METHODS: For hair growth experiment, shaved dorsal skins of C57BL/6 mice were topically applied with vehicle, RGO, RGO's major compounds, or minoxidil for consecutive 21 days and skin tissues were examined the hair growth promoting capacity. For skin protection experiment, SKH-1 hairless mice were topically applied with vehicle or RGO twice a day for three days prior to exposure to UVC radiation at 20 kJ/cm2. Skin tissues were collected to evaluate skin protective effects of RGO. RESULTS: Topical application of RGO to C57BL/6 mice effectively promoted hair regeneration by inducing early telogen-to-anagen transition and significantly increasing the density and bulb diameter of hair follicles. Major compounds, including linoleic acids and β-sitosterol, contributed to RGO-promoted hair growth. Treatment with RGO as well as its major components upregulated expression of hair growth-related proteins. Furthermore, in SKH-1 hairless mice, RGO had a protective effect against UVC-induced skin damage by inhibiting inflammation and apoptosis, as well as inducing cytoprotective systems. CONCLUSION: The

OBJECTIVES: Terminalia arjuna (TA) has been widely used as folk medicine since ancient times. Apart from its therapeutic properties it also has anti-spermatogenic activity, but its effectiveness and mode of action on male gonadal activity remains to be revealed. METHODS: TA bark extract was dissolved in 1% dimethyl sulfoxide and applied in primary Leydig cell culture from rat testis in dose dependent manner. After 24 h of treatment cellular toxicity marker, cytokines, steroid 5-alpha-reductase 1 (SRD5A1) and androgen receptor (AR) were measured. RESULTS: Present study first proposed the cytotoxic impacts of TA on Leydig cells via leakage of lactate dehydrogenase and inflammatory responses by altering the pro- and anti-inflammatory cytokines in dose-dependent-manner. Furthermore, down regulation of SRD5A1 and AR indicated inhibition of normal steroidogenesis which well corroborated with cytotoxity and inflammation related parameters to promote damage of Leydig cell function. Nevertheless, it can be speculated that the inhibition of normal steroidogenesis and thereby spermatogenesis induced by TA is possibly due to the presence of β-sitosterol. CONCLUSIONS: Therefore, the dose and duration of treatment should be carefully monitored in cases of its medicinal uses and longer duration should be avoided to protect reproductive health and fertility. © 2021 Walter de Gruyter GmbH, Berlin/Boston.

ETHNOPHARMACOLOGICAL RELEVANCE: Prunus mira Koehne (P. mira, Tibetan name: ཁམབུ།) is a kind of medicinal plant commonly used in Tibetan areas. The classic Tibetan medicine book Jingzhu Materia Medica records that "the nut oil from P. mira is used to cure loss of hair, eyebrows, beards, etc." but the clinical experience has not been explored. Hair loss (alopecia) is a skin disease that becomes a common concern in Chinese society since it affects the appearance of a person. This paper studies the effectiveness of nut oil from P. mira in promoting hair growth and its working mechanism. MATERIALS AND METHODS: The content of different components in the nut oil from P. mira was determined by HPLC. Two hair removal methods (sodium sulfide and hair removal cream) were used to study the effect of different doses on hair growth in KM mice. Then select the effective group, and use C57BL/6 mice to determine the number of hair follicles, dermal thickness, β-catenin, GSK3β and Wnt10 b mRNA and protein expression. RESULTS: The contents of α-tocopherol, β-sitosterol, Vitamin E, Oleic acid and linoleic acid in nut oil from P. mira growing in 12 different regions were determined by HPLC. The linearity reached 0.999. The RSD of precision, stability, repeatability, and sample recovery was less than 3%. The dose-effect relationship suggested that 30.13 and 14.07 mg medicinal material·(cm2

During the last years, pharmaceutical innovations in primary care are dramatically less frequent and will be even more rare in the next future. In this context, preclinical and clinical research oriented their interest toward natural compounds efficacy and safety, supporting the development of a new "nutraceutical" science. Medicinal plants, in the form of plant parts or extracts of them, are commonly used for the treatment of prostate diseases such as benign hypertrophy, prostatitis and chronic pelvic pain syndrome. The pharmacological properties searched for the treatment of prostatic diseases are anti-androgenic, anti-estrogenic, antiproliferative, antioxidant and anti-inflammatory. The most studied and used medicinal plants are Serenoa repens, Pygeum africanum and Urtica dioica. Other promising plants are Cucurbita pepo, Epilobium spp, Lycopersum esculentum, Secale cereale, Roystonea regia, Vaccinium macrocarpon. In parallel, epidemiological studies demonstrated that diet may play an important role on incidence and development of prostatic diseases. The Mediterranean diet is rich of elements with anti-oxidant properties that act as a protective factor for prostatic cancer. Similarly, low intake of animal protein, high intake of fruits and vegetable, lycopene and zinc are a protective factor for benign prostatic hyperplasia (BPH). Serenoa repens in the treatment of symptoms of BPH has been tested either alone or, more frequently, in combination with other medicinal plants, alpha-blockers and inhibitors of 5- alpha reductase (5-ARI). Recent meta-analyses found the effectiveness of Serenoa repens similar or inferior of that of finasteride and tamsulosin but clearly higher than that o

Pumpkin seed oil (PSO) provides many health benefits including antioxidant, cardiovascular health boost, treatment of benign prostatic hyperplasia (BPH), and reduction of hair loss. The main objective of this study was to design a suitable formulation of niosomes encapsulated PSO for topical delivery. Formulation of PSO-loaded niosomes was optimised by altering the types of surfactant and the amount of PSO:surfactant:cholesterol. The developed PSO-loaded niosomes were spherical shape with the size range of 138-366 nm. The niosomes formulated with Tween 20 provided the smallest particle size. An increase in the ratio of PSO:surfactant:cholesterol from 2:2:1 to 2:4:1 led to reduction of the particle size of the niosomes. The PSO-loaded niosomes formulation F1 (PSO:Tween 20:cholesterol = 2:2:1) provided the highest percent entrapment efficacy at 75.99 ± 14.65%. The in vitro release study suggested that the release mechanism was followed Korsmeyer-Peppas. The physical stability study indicated good stability over 3 months of storage at 30 °C.

Hair loss (alopecia) is a universal problem for numerous people in the world. The present study was conducted to investigate the effects of red ginseng oil (RGO) and its major components on hair re-growth using testosterone (TES)-induced delay of anagen entry in C57BL/6 mice and their mechanisms of action. Seven-week-old C57BL/6 mice were daily treated with TES for 1 h prior to topical application of 10% RGO, 1% linoleic acid (LA), 1% β-sitosterol (SITOS), or 1% bicyclo(10.1.0)tridec-1-ene (BICYCLO) once a day for 28 days. Hair regenerative capacity was significantly restored by treatment of RGO and its major compounds in the TES-treated mice. Histological analysis showed that RGO along with LA and SITOS but not BICYCLO promoted hair growth through early inducing anagen phase that was delayed by TES in mice. Treatment of mice with RGO, LA, or SITOS up-regulated Wnt/β-catenin and Shh/Gli pathways-mediated expression of genes such as β-catenin, Lef-1, Sonic hedgehog, Smoothened, Gli-1, Cyclin D1, and Cyclin E in the TES-treated mice. In addition, RGO and its major components reduced the pro

Objective: To evaluate the effectiveness of a novel oral supplement, Forti5®, containing green tea extract, omega 3 and 6 fatty acids, cholecalciferol, melatonin, beta-sitosterol, and soy isoflavones, and in the management of subjects with androgenetic alopecia. Design: A prospective case series of 10 subjects. Setting: Open-label, evaluator-blinded, proof-of-concept study. Participants: Ten adult subjects with androgenetic alopecia completed the study. Subjects were not allowed to use oral or topical hair growth products in the 24 weeks preceding the study or during the study. The nutritional supplement was administered at a dosage of two tablets daily for 24 weeks. Measurements: Clinical evaluations were performed at baseline and at 24 weeks. Efficacy was evaluated using hair mass index measured by cross section trichometer, terminal hair count measured with dermoscopy and Investigator Global Photography Assessment. Results: Overall 80 percent of subjects (8/10) were rated as improved after 24 weeks of supplementation (mean change of +1.4 equivalent to slightly-to-moderately increased). Forty percent of subjects (4/10) were rated as moderately improved (2+), and 10 percent (1/10) were rated as greatly improved (3+). There was a significant improvement in terminal hair count (mean increase of 5.9% or 4.2 more terminal hairs in the area examined, p=0.014) and in Hair Mass Index (mean increase of 9.5% or 4.5 higher Hair Mass Index, p=0.003). Conclusion: These preliminary results indicate that Forti5® a novel

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional medicine has used Uvaria rufa Blume as an ethnomedicinal plant for treating fever, skin allergies, intestinal ulcers and prostate disorders including BPH. However, no scientific evidence supports the traditional use. AIM OF THE STUDY: This study aimed to evaluate the therapeutic potential of U. rufa on BPH using in vitro and in vivo models. MATERIALS AND METHODS: In vitro studies screened the efficacy of a 5α-reductase (5αR) inhibition and antioxidant activity of petroleum ether, ethyl acetate, ethanol and aqueous extracts from the stem of U. rufa. Phytochemical screening was performed to determine the active compound using high-performance liquid chromatography (HPLC). Ethyl acetate extract (UR-EtOAc) of U. rufa was used to evaluate the therapeutic efficacy in vivo models. BPH was induced by subcutaneous injection of testosterone propionate (3mg/kg) to male rats for 30 days. After 30 days of oral administration of UR-EtOAc at doses of 10 and 20mg/kg and finasteride at a dose of 1mg/kg, the prostate weight, prostate index (PI), testosterone and androgen receptor (AR) levels, and histopathological alteration of prostate gland were determined. Also, oxidative status and toxicity indices were ass

Androgenetic alopecia (AGA) affects approximately 70% of men and 40% of women in an age-dependent manner and is partially mediated by androgen hormones. Benign prostatic hyperplasia (BPH) similarly affects 50% of the male population, rising by 10% each decade. Finasteride inhibits 5-alpha reductase (5AR) and is used to treat both disorders, despite offering limited clinical benefits accompanied by significant adverse side effects. Building on our previous work demonstrating the efficacy of naturally derived 5AR inhibitors (such as stigmasterol and beta sitosterol), we hypothesize that targeting 5AR as well as inflammatory pathways may yield improved efficacy in AGA and BPH. Here we address these dual pathomechanisms by examining the potency of a novel composition using in vitro assays of representative cell lines for AGA (hair follicle dermal papilla cells) and BPH (LNCaP prostate cells), respectively. Exposure of cells to the novel test composition down-regulated mRNA expression profiles characteristic of both disease processes, which outperformed finasteride. Changes in mRNA expression were corroborated at the protein level as assessed by western blotting. These studies provide proof of concept that novel, naturally derived compositions simultaneously targeting 5AR and inflammatory mediators may represent a rational approach to treating AGA and BPH. Copyright © 2016 John Wiley & Sons, Ltd.