High-dose atorvastatin causes regression of endometriotic implants: a rat model

Atorvastatin exerts dual effects of lesion regression and ovarian protection in the prevention and treatment of endometriosis

Endometriosis is a frequent, chronic, estrogen-dependent and inflammatory gynecological disease leading to pain and infertility. Clinical and metabolic studies reveal that patients with endometriosis are susceptible to hyperlipemia and lipid dysfunction, putting them at ascending risk of cardiovascular diseases. Statins constitute a group of cholesterol-lowering drugs with pleiotropic effects. A plethora of researches have proved their ability to inhibit the growth of ectopic lesions in endometriosis. However, concerns exist about their possible adverse effects on ovarian function. This study aimed to investigate the possible effect of atorvastatin on the ovarian endocrine function and fertility capacity in the prevention and treatment of endometriosis. Here, 5 mg/kg atorvastatin was intraperitoneally injected to the endometriosis mice once a day for consecutive fourteen days during and after the development of endometriotic implants. The results indicated that atorvastatin not only led to regression of the ectopic lesions, but also caused no discernible harm to the ovary for both the preventive and the therapeutic models. In addition, it elicited a protective effect on the ovarian reserve and fertility possibly by reducing inflammation in the ovary. Hence, atorvastatin could be a promising drug for endometriosis prevention and treatment.

The latest advances in the pharmacological management of endometriosis

INTRODUCTION

Endometriosis is a benign disease, characterized by a wide range of symptoms and different degrees of severity, which is why therapy should be individually adapted to the patient's needs. Over the years, a lot of research has gone into finding new therapeutic approaches for this enigmatic disease.

AREAS COVERED

This review presents the latest advances in pharmacological management of endometriosis and is solely focused on studies published from 2010 to 2021.

EXPERT OPINION

Clinicians and researchers are constantly searching for new therapeutic strategies for endometriosis patients. As there are well-established treatments, however, any new medication should fulfill at least one of the three criteria: increased efficacy, comparable efficacy but a better safety profile, or treatments that have a lack of accompanying contraceptive effects that are seen in most endometriosis treatments. While some new substances show promising results, further studies are needed to demonstrate the fulfillment of one of the above-mentioned criteria.

Endometriosis-Associated Angiogenesis and Anti-angiogenic Therapy for Endometriosis

Endometriosis is a known estrogen-dependent inflammatory disease affecting reproductive-aged women. Common symptoms include pelvic pain, dysmenorrhea, dyspareunia, heavy menstrual bleeding, and infertility. The exact etiology of endometriosis is largely unknown, and, thus, the diagnosis and treatment of endometriosis are challenging. A complex interplay of many molecular mechanisms is thought to aid in the progression of endometriosis, most notably angiogenesis. This mini-review examines our current knowledge of the molecular etiology of endometriosis-associated angiogenesis and discusses anti-angiogenic therapy, in the blockade of endometriosis-associated angiogenesis, as potential non-hormonal therapy for the treatment of endometriosis.

BNO 1095, a Standardized Dry Extract from the Fruits of Vitex agnus-castus, Impairs Angiogenesis-related Endothelial Cell Functions In Vitro

BNO 1095, a standardized dry extract from the fruits of Vitex agnus-castus, represents an approved herbal medicinal product for the treatment of premenstrual syndrome. Angiogenesis, the formation of new blood vessels from pre-existing capillaries, plays a major role in physiological situations, such as wound healing or tissue growth in female reproductive organs, but it is also of great importance in pathophysiological conditions such as chronic inflammatory diseases or cancer. Angiogenesis is a highly regulated multi-step process consisting of distinct key events that can be influenced pharmacologically. Few studies suggested anti-angiogenic actions of V. agnus-castus fruit extracts in in vivo and ex vivo models. Here, we provide for the first time profound in vitro data on BNO 1095-derived anti-angiogenic effects focusing on distinct angiogenesis-related endothelial cell functions that are inevitable for the process of new blood vessel formation. We found that V. agnus-castus extract significantly attenuated undirected and chemotactic migration of primary human endothelial cells. Moreover, the extract efficiently inhibited endothelial cell proliferation and reduced the formation of tube-like structures on Matrigel. Of note, the treatment of endothelial cell spheroids almost blocked endothelial sprouting in a 3D collagen gel. Our data present new and detailed insights into the anti-angiogenic actions of BNO 1095 and, therefore, suggest a novel scope of potential therapeutic applications of the extract for which these anti-angiogenic properties are required.

The Effect of Novel Medical Nonhormonal Treatments on the Angiogenesis of Endometriotic Lesions

Importance

Irrespective of the precise mechanisms leading to endometriosis, angiogenesis is essential for the establishment and long-term proliferation of the disease. As current surgical and medical management options for women with endometriosis have substantial drawbacks and limitations, novel agents are needed and molecules targeting the angiogenic cascade could serve as potential candidates.

Objective

Our aim was to review current data about the role of angiogenesis in the pathophysiology of endometriosis and summarize the novel antiangiogenic agents that could be potentially used in clinical management of patients with endometriosis.

Evidence Acquisition

Original research and review articles were retrieved through a computerized literature search.

Results

Loss of balance between angiogenic activators and suppressors triggers the nonphysiological angiogenesis observed in endometriotic lesions. Several proangiogenic mediators have been identified and most of them have demonstrated increased concentrations in the peritoneal fluid and/or serum of women with endometriosis. Among the antiangiogenic molecules, anti-vascular endothelial growth factor agents, dopamine agonists, romidepsin, and statins have shown the most promising results so far.

Conclusions and Relevance

Given the limitations of current treatments of endometriosis, there is a need for novel, more efficient agents. Antiangiogenic molecules could be used potentially in clinical management of women with endometriosis; however, their safety and efficiency should be carefully assessed prior to that. Further large prospective trials in humans are needed before any treatment is introduced into daily clinical practice.

Effects of atorvastatin and resveratrol against the experimental endometriosis; evidence for glucose and monocarboxylate transporters, neoangiogenesis

The current study was conducted to investigate the therapeutic effects of atorvastatin (ATV) and resveratrol (RVT) in sole and simultaneous forms of administration against the symbiosis between glucose transporters 1 and 3 (GLUT-1 and GLUT-3), monocarboxylate transporters 1 a and 4 (MCT-1 and MCT-4) and neovascularization in ectopic endometrial tissue (EET). For this purpose, the experimental endometriosis was induced in 24 virgin female Wistar rats, and then the rats were divided into non-treated endometriosis-induced (ENDO-sole), AVT-treated (5 mg kg-1), RVT-treated (40 mg kg-1) and AVT +RVT-treated groups (n = 6 rats in each group). Following 28 days from the experimental endometriosis induction, the EETs were collected and the EETs size, neovascularization ratio, and expression levels of GLUT-1, GLUT-3, MCT-1, and MCT-4 were analyzed by qRT-PCR and immunohistochemistry (IHC). The AVT and RVT sole and simultaneous-treated animals exhibited decreased EET sizes and neovascularization. Moreover, the mRNA levels of GLUT-1, GLUT-3, MCT-1, and MCT-4, as well as GLUT-1⁺, GLUT-3⁺, and MCT-4⁺ cells distribution per mm² of tissue were decreased in AVT and RVT sole and simultaneous-treated groups. Our findings showed that the AVT and RVT, especially in the simultaneous form of administration, could decrease the neovascularization development in the EETs by suppressing the GLUTs (1 and 3) and MCTs (1 and 4) expressions. Therefore, it can be concluded that the simultaneous administration of AVT and RVT can inhibit the EET's establishment and development through suppressing glycolysis and neovascularization.

The ameliorative effect of atorvastatin on serum testosterone and testicular oxidant/antioxidant system of HFD-fed male albino rats

Background: There is a mutual effect between central obesity and low total serum testosterone. Moreover, oxidative stress acts as a bridge between obesity and its complications. Taken together, we aimed to evaluate whether atorvastatin (AS), a cholesterol-lowering drug, has protective potential against high fat diet (HFD)-induced low fertility, which was exemplified in serum testosterone determination. Moreover, we aimed to deduce a putative mechanism of action through evaluation of the testicular oxidant/antioxidant system. Methods: Adult male albino Wistar rats ( Rattus norvegicus albinus) were divided into three groups: 1) normal control group, rats were fed a normal diet for four weeks; 2) HFD group, rats were fed an HFD for four weeks; and 3) AS group, rats were fed an HFD and 5 mg/kg/day atorvastatin for the last two weeks of the experiment. Serum atherogenic index, testosterone, and thyroid stimulating hormone were estimated. Moreover, testicular reduced glutathione and malondialdehyde contents, as well as glutathione-S-transferase, superoxide dismutase, and glutathione reductase activities were also determined. The statistical differences were analyzed using analysis of variance (ANOVA). Results: AS ameliorated the increased level of serum atherogenic index induced by an HFD, as well as testicular malonaldehyde and reduced glutathione levels. On the other hand, AS increased the depleted level and activity of serum testosterone and testicular glutathione reductase, respectively, induced by HFD. Conclusion: The ameliorative effect of AS on the deteriorated level of total serum testosterone induced by HFD might partially be due to oxidant/antioxidant disturbance. Further studies should be carried out to evaluate mTOR pathway contribution, which could enable researchers to deduce drugs targeting members of the oxidant/antioxidant system and/or mTOR pathway to ameliorate putative HFD-induced low fertility.

New therapeutic approaches for endometriosis besides hormonal therapy

Supplemental Digital Content is available in the text

Objective:

Endometriosis is a common gynecologic disease that frequently leading to chronic pelvic pain, severe dysmenorrhea, and subfertility. As first-line hormonal treatment can interfere with ovulation and may cause recurrent pelvic pain, exploration of new non-hormonal therapeutic approaches becomes increasingly necessary. This review aimed to evaluate the pre-clinical and clinical efficacy and safety of non-hormonal treatment for endometriosis

Data sources:

Databases including PubMed, Embase, Cochrane Library, SINOMED, ClinicalTrials.gov, and Google Scholar were searched up to October 2019, using search terms “endometriosis” and “non-hormonal therapy.”

Study selection:

Twenty-four articles were reviewed for analysis, including nine animal studies and 15 human trials; all were published in English.

Results:

Twenty-four articles were identified, including 15 human trials with 861 patients and nine animal studies. Some agents have been evaluated clinically with significant efficacy in endometriosis-related pelvic pain and subfertility, such as rofecoxib, etanercept, pentoxifylline, N-palmitoylethanolamine, resveratrol, everolimus, cabergoline (Cb2), and simvastatin. Other drugs with similar pharmacological properties, like parecoxib, celecoxib, endostatin, rapamycin, quinagolide, and atorvastatin, have only been tested in animal studies.

Conclusions:

Clinical data about most of the non-hormonal agents are not sufficient to support them as options for replacement therapy for endometriosis. In spite of this, a few drugs like pentoxifylline showed strong potential for real clinical application.

Synergistic and protective effect of atorvastatin and amygdalin against histopathological and biochemical alterations in Sprague-Dawley rats with experimental endometriosis

The aim of the present study was to evaluate the protective effects of combined atorvastatin and amygdalin in a rat model of endometriosis. Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2) and MMP-9 levels in the peritoneal fluid were determined. The expression of TNF-α, IL-6, MMP-2, and MMP-9 mRNA, and the levels of lipid peroxidation, reduced glutathione (GSH), superoxide dismutase (SOD), catalase, and glutathione peroxidase (Gpx) were measured. Histopathological analysis was also conducted. The results showed that peritoneal TNF-α, IL-6, MMP-2, and MMP-9 levels were reduced by > 50%, and mRNA expression was decreased. Lipid peroxidation was considerably reduced, while GSH, SOD, Gpx, and catalase levels increased by > 40%. Reductions in leukocyte infiltration and fibrosis following treatment were also observed. Thus, our study suggested that combined treatment consisting of atorvastatin and amygdalin attenuates endometriosis. A detailed investigation of molecular mechanism of atorvastatin and amygdalin in endometriosis is needed.

Lipophilic statins inhibit growth and reduce invasiveness of human endometrial stromal cells

PURPOSE

To compare effects of lipid-soluble statins (simvastatin, lovastatin, atorvastatin) and water-soluble statin (pravastatin) on growth and invasiveness of human endometrial stromal (HES) cells.

METHODS

Endometrial biopsies were collected during the proliferative phase from five volunteers. HES cells were isolated and cultured in the absence or in the presence of simvastatin, lovastatin, atorvastatin, and pravastatin. Effects of statins on DNA synthesis, cell viability, activity of caspases 3/7 and invasiveness were evaluated.

RESULTS

The proliferation of HES cells was significantly decreased by simvastatin (by 47-89%), lovastatin (by 46-78%), and atorvastatin (by 21-48%) in a concentration-dependent manner. Activity of executioner caspases 3/7 was significantly increased by simvastatin (by 10-25%), lovastatin (by 19%) and atorvastatin (by 7-10%) in a concentration-dependent manner. The greatest effects were observed in response to simvastatin. Accounting for the effects of statins on cell number, the invasiveness of HES cells was significantly decreased in cells treated with simvastatin (by 49%), lovastatin (by 54%), and atorvastatin (by 53%). Pravastatin had little or no effects on any of the tested endpoints.

CONCLUSIONS

Present findings demonstrate that only lipid-soluble among tested statins were effective in inhibition of growth and invasiveness of HES cells. These findings may have clinical relevance in treatment of endometriosis.

Anti-Angiogenic Alternative and Complementary Medicines for the Treatment of Endometriosis: A Review of Potential Molecular Mechanisms

Endometriosis is caused by the growth or infiltration of endometrial tissues outside of the endometrium and myometrium. Symptoms include pain and infertility. Surgery and hormonal therapy are widely used in Western medicine for the treatment of endometriosis; however, the side effects associated with this practice include disease recurrence and menopause, which can severely influence quality of life. Angiogenesis is the main biological mechanism underlying the development of endometriosis. Numerous natural products and Chinese medicines with potent anti-angiogenic effects have been investigated, and the molecular basis underlying their therapeutic effects in endometriosis has been explored. This review aims to describe natural products and compounds that suppress angiogenesis associated with endometriosis and to assess their diverse molecular mechanisms of action. Furthermore, this review provides a source of information relating to alternative and complementary therapeutic products that mediate anti-angiogenesis. An extensive review of the literature and electronic databases, such as the China National Knowledge Infrastructure, PubMed, and Embase, was conducted using the keywords 'endometriosis,' 'traditional Chinese medicine,' 'Chinese herbal medicine,' 'natural compounds,' and 'anti-angiogenic' therapy. Anti-angiogenic therapy is an emerging strategy for the treatment of endometriosis. Natural anti-angiogenic products and Chinese medicines provide several beneficial clinical effects, including pain relief. In this review, we summarize clinical trials and experimental studies of endometriosis using natural products and Chinese medicines. In particular, we focus on anti-angiogenic products and alternative and complementary medicines for the treatment of endometriosis and additionally examine their therapeutic efficacy and mechanisms of action. Anti-angiogenic natural products and/or compounds provide a new approach for the treatment of endometriosis. Future work will require randomized trials with larger numbers of subjects, as well as long-term follow-up to confirm the findings described here.

Investigational drugs for the treatment of endometriosis, an update on recent developments

INTRODUCTION

Endometriosis is a hormone-dependent benign chronic disease that requires a chronic medical therapy. Although currently available drugs are efficacious in treating endometriosis-related pain, some women experience partial or no improvement. Moreover, the recurrence of symptoms is expected after discontinuation of the therapies. Currently, new drugs are under intense clinical investigation for the treatment of endometriosis.

AREAS COVERED

This review aims to offer the reader a complete and updated overview on new investigational drugs and early molecular targets for the treatment of endometriosis. The authors describe the pre-clinical and clinical development of these agents.

EXPERT OPINION

Among the drugs under investigation, late clinical trials on gonadotropin-releasing hormone antagonists (GnRH-ant) showed the most promising results for the treatment of endometriosis. Aromatase inhibitors (AIs) are efficacious in treating endometriosis related pain symptoms but they cause significant adverse effects that limit their long-term use. New targets have been identified to produce drugs for the treatment of endometriosis, but the majority of these new compounds have only been investigated in laboratory studies or early clinical trials. Thus, further clinical research is required in order to elucidate their efficacy and safety in human.

Effect of simvastatin on baboon endometriosis

Endometriosis, a common disorder affecting women of reproductive age, is characterized by ectopic growth of the endometrial tissues, altered steroid hormone response, and inflammation. Previous studies revealed that statins, selective inhibitors of the key step of mevalonate pathway, inhibit growth of endometrial stromal cells in vitro and reduce endometriotic lesions in murine models of endometriosis. This study evaluated the effects of simvastatin on the development of endometriosis in a baboon model of this disease. Sixteen baboons were randomly assigned to the treatment group (simvastatin, 20 mg daily) or to the control group. Endometriotic lesions were evaluated by laparoscopy after 3 months. The volume of red, orange-red, and white endometriotic lesions was significantly reduced by 78% in animals treated with simvastatin. The expression of a marker of proliferation, proliferating cell nuclear antigen (PCNA), was significantly reduced in animals receiving simvastatin in red lesions, white lesions, black lesions, and in adhesions. Simvastatin was also associated with an increase in the expression of estrogen receptor alpha in red lesions, and a decrease in the expression of estrogen receptor beta in black lesions, in adhesions, and in eutopic endometrium. Furthermore, simvastatin significantly reduced the expression of neopterin, a marker of inflammation, oxidative stress, and immune system activation. Collectively, the present findings indicate that the inhibition of the mevalonate pathway by simvastatin reduces the risk of developing endometriosis in the primate model of this disease by decreasing the growth of endometrial lesions, by modulating the expression of genes encoding for estrogen receptors, and by reducing inflammation.

Serum MicroRNA Biomarkers Regulated by Simvastatin in a Primate Model of Endometriosis

Endometriosis is a chronic inflammatory and estrogen-dependent disease that causes pain and infertility in reproductive-aged women. Due to the delay in diagnosis, there is a pressing need for accurate biomarkers. Detection of serum noncoding RNA molecules such as microRNAs (miRNAs) shows promise as a noninvasive diagnostic strategy; we previously identified miRNAs that are highly sensitive and specific biomarkers for the disease. In this study, we investigate the expression of these miRNAs in a nonhuman primate model of endometriosis. As part of a pilot study evaluating simvastatin for the treatment of endometriosis, the disease was induced in 16 baboons by induction laparoscopy and the animals were divided into 2 groups. One group was treated with simvastatin for 90 days, while the second group received vehicle only. Endometriosis was evaluated after 3 months by laparoscopy. Serum samples were analyzed for 9 circulating miRNAs using quantitative real time-polymerase chain reaction, focusing on the miRNAs we found to be dysregulated in human endometriosis. In the simvastatin-treated endometriosis group, levels of miR-150-5p and miR-451a were decreased, while miR-3613-5p levels were increased compared to the untreated endometriosis group. The changes in circulating miRNA expression patterns parallel our previous results in human patients and show that specific miRNAs correlate with endometriosis severity and reverted toward control expression levels after simvastatin treatment. This is the first report showing serum miRNA expression normalized in response to endometriosis treatment, supporting the potential for this class of biomarkers to be used both to diagnose endometriosis and to monitor its progression and response to therapy.

Therapeutic Roles of Statins in Gynecology and Obstetrics: The Current Evidence

INTRODUCTION

Statins are a class of drugs, which act by inhibiting the rate-limiting enzyme of cholesterol biosynthesis (3-hydroxy-3-methyl-glutaryl-CoA reductase). The inhibition of mevalonate synthesis leads to subsequent inhibition of downstream products of this pathway, which explains the pleiotropic effects of these agents in addition to their well-known lipid-lowering effects. Accumulating evidence suggests that statins might be beneficial in various obstetric and gynecologic conditions.

METHODS

Literature searches were performed in PubMed and EMBASE for articles with content related to statins in obstetrics and gynecology. The findings are hereby reviewed and discussed.

RESULTS

Inhibition of mevalonate pathway leads to subsequent inhibition of downstream products such as geranyl pyrophosphate, farnesyl pyrophosphate, and geranylgeranyl pyrophosphate. These products are required for proper intracellular localization of several proteins, which play important roles in signaling pathways by regulating membrane trafficking, motility, proliferation, differentiation, and cytoskeletal organization. The pleiotropic effects of statins can be summarized in 4 categories: antiproliferative, anti-invasive, anti-inflammatory, and antiangiogenic. The growing body of evidence is promising for these agents to be beneficial in endometriosis, polycystic ovary syndrome, adhesion prevention, ovarian cancer, preeclampsia, and antiphospholipid syndrome. Although in vivo studies showed varying degrees of benefit on fibroids and preterm birth, appropriately designed clinical trials are needed to make definitive conclusions.

CONCLUSION

Statins might play a role in the treatment of endometriosis, polycystic ovary syndrome, adhesion prevention, ovarian cancer, preeclampsia, and antiphospholipid syndrome.

New developments in the medical treatment of endometriosis

Endometriosis affects 1 in 10 women of reproductive-age. The current treatments are surgical and hormonal but have limitations, including the risk of recurrence, side effects, contraceptive action for women who desire pregnancy, and cost. New treatments include gonadotropin-releasing hormone analogues, selective progesterone (or estrogen) receptor modulators, aromatase inhibitors, immunomodulators, and antiangiogenic agents. Further research is needed into central sensitization, local neurogenesis, and the genetics of endometriosis to identify additional treatment targets. A wider range of medical options allows for the possibility of precision health and a more personalized treatment approach for women with endometriosis.

Statin use and uterine fibroid risk in hyperlipidemia patients: a nested case-control study

BACKGROUND

Statins are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors primarily used for treatment of hyperlipidemia. Recently, they have been shown to inhibit proliferation of uterine fibroid cells and inhibit tumor growth in fibroid animal models.

OBJECTIVE

We sought to examine the association between statin use and the risk of uterine fibroids and fibroid-related symptoms in a nationally representative sample of commercially insured women diagnosed with hyperlipidemia.

STUDY DESIGN

We performed a nested case-control study of >190,000 women enrolled in one of the nation's largest commercial health insurance programs. From a cohort of women aged 18-65 years diagnosed with hyperlipidemia from January 2004 through March 2011, we identified 47,713 cases (women diagnosed with uterine fibroids) and 143,139 controls (women without uterine fibroids) matched at a 1:3 ratio on event/index date (month and year) and age (±1 year). We used conditional and unconditional logistic regression to calculate odds ratios and 95% confidence intervals for the risk of uterine fibroids and fibroid-related symptoms associated with prior use of statins.

RESULTS

Exposure to statins within 2 years before the event/index date was associated with a decreased risk of uterine fibroids (odds ratio, 0.85; 95% confidence interval, 0.83-0.87). In a separate subanalysis restricted to cases, statin users had a lower likelihood of having menorrhagia (odds ratio, 0.88; 95% confidence interval, 0.84-0.91), anemia (odds ratio, 0.84; 95% confidence interval, 0.79-0.88), or pelvic pain (odds ratio, 0.85; 95% confidence interval, 0.81-0.91) and of undergoing myomectomy (odds ratio, 0.76; 95% confidence interval, 0.66-0.87) compared to nonusers.

CONCLUSION

The use of statins was associated with a lower risk of uterine fibroids and fibroid-related symptoms. Further studies, including randomized controlled trials, may be warranted.

Novel effects of simvastatin on uterine fibroid tumors: in vitro and patient-derived xenograft mouse model study

OBJECTIVE

Uterine leiomyomas represent a common gynecologic problem with no satisfactory long-term medical treatment. The purpose of this study is to examine the effects of simvastatin on uterine leiomyoma, both in vitro and in vivo.

STUDY DESIGN

This is a laboratory-based experimental study. For in vitro studies, we used human and rat leiomyoma cells. For in vivo studies, we used immunodeficient mice supplemented with estrogen/progesterone pellets xenografted with human leiomyoma tissue explant.

RESULTS

For in vitro studies, cells were treated with different concentrations of simvastatin for 48 hours. Simvastatin induced dose-dependent apoptosis in leiomyoma cells as measured by a fluorometric caspase-3 activity assay, and inhibited proliferation as demonstrated by an (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay (both were significant at 5 and 10 μM). In addition, simvastatin decreased Akt signaling pathway phosphorylation as examined using Western blot analysis. For in vivo studies, animals were treated for 28 days with simvastatin (20 μg/gm body weight/day) vs vehicle control. The treatment inhibited tumor growth as measured weekly using calipers and/ or ultrasound (P < .01). Finally, simvastatin decreased expression of the proliferation marker Ki67 in xenograft tumor tissue as examined by immunohistochemistry (P = .02).

CONCLUSION

Simvastatin can be a promising treatment for uterine leiomyoma. Further studies, including pharmacokinetic and drug delivery studies, are required.

Pathogenesis of Endometriosis: Roles of Retinoids and Inflammatory Pathways

Endometriosis is a nonmalignant, but potentially metastatic, gynecological condition manifested by the extrauterine growth of inflammatory endometrial implants. Ten percent of reproductive-age women are affected and commonly suffer pelvic pain and/or infertility. The theories of endometriosis histogenesis remain controversial, but retrograde menstruation and metaplasia each infer mechanisms that explain the immune cell responses observed around the ectopic lesions. Recent findings from our laboratories and others suggest that retinoic acid metabolism and action are fundamentally flawed in endometriotic tissues and even generically in women with endometriosis. The focus of our ongoing research is to develop medical therapies as adjuvants or alternatives to the surgical excision of these lesions. On the basis of concepts put forward in this review, we predict that the pharmacological actions and anticipated low side-effect profiles of retinoid supplementation might provide a new treatment option for the long-term management of this chronic and debilitating gynecological disease.

Endometriosis: alternative methods of medical treatment

Endometriosis is an inflammatory estrogen-dependent disease defined by the presence of endometrial glands and stroma at extrauterine sites. The main purpose of endometriosis management is alleviating pain associated to the disease. This can be achieved surgically or medically, although in most women a combination of both treatments is required. Long-term medical treatment is usually needed in most women. Unfortunately, in most cases, pain symptoms recur between 6 months and 12 months once treatment is stopped. The authors conducted a literature search for English original articles, related to new medical treatments of endometriosis in humans, including articles published in PubMed, Medline, and the Cochrane Library. Keywords included "endometriosis" matched with "medical treatment", "new treatment", "GnRH antagonists", "Aromatase inhibitors", "selective progesterone receptor modulators", "anti-TNF α", and "anti-angiogenic factors". Hormonal treatments currently available are effective in the relief of pain associated to endometriosis. Among new hormonal drugs, association to aromatase inhibitors could be effective in the treatment of women who do not respond to conventional therapies. GnRH antagonists are expected to be as effective as GnRH agonists, but with easier administration (oral). There is a need to find effective treatments that do not block the ovarian function. For this purpose, antiangiogenic factors could be important components of endometriosis therapy in the future. Upcoming researches and controlled clinical trials should focus on these drugs.

Statins as Targeted "Magical Pills" for the Conservative Treatment of Endometriosis: May Potential Adverse Effects on Female Fertility Represent the "Dark Side of the Same Coin"? A Systematic Review of Literature

The aim of the study was to analyze all the available evidence from both in vitro and in vivo studies regarding the efficacy of statin therapy in the treatment of endometriosis, evaluating the potential efficacy, side effects, and contraindications of their administration in humans. We focused on defining the potential benefits that the administration of statins may have on patients affected by endometriosis and the possible adverse effects of such a therapy on ovarian function and fertility profile. According to our article selection criteria, we included in the review in vitro and in vivo studies performed on human or animal models. The systematic review of literature identified 24 eligible articles, 12 of which reported evidence regarding the effects of statins on endometrial/endometriotic cells and 12 regarding their effects on ovarian function and fertility. All articles seem to emphasize the utility of statin administration in the treatment of endometriosis due to their anti-proliferative/proapoptotic effects, their ability to reduce cell viability and migration, and the inhibition of angiogenesis and anti-inflammatory activities. Regarding the potential adverse effects on gonadal activities, steroidogenesis and fertility function, no conclusive data were collected in human models (excluding women affected by polycystic ovary syndrome in which significant decline of androgen levels was reported after statin treatment), while contrasting results were reported by studies conducted in in vitro and in vivo in animal models. Despite evidence supporting statins as the potential therapeutic agent for a targeted conservative treatment of endometriosis, the uncertainties regarding their impact on gonadal function may not define them as an appropriate therapy for all young fertile women.

Novel agents for the medical treatment of endometriosis

PURPOSE OF REVIEW

Current medical treatments for endometriosis-associated pain, including oral contraceptives, progestins and GnRH agonists, are partially effective and have significant side-effects. The purpose of this review is to present new hormonal and nonhormonal treatment for endometriosis.

RECENT FINDINGS

At present, the ideal drug that can prevent, inhibit or stop development of endometriosis, reduce associated pain or infertility and allow conception does not exist. New drugs in development for endometriosis modulate GnRH, estrogen and/or progesterone receptors, or target endometriosis-associated inflammation, angiogenesis, adhesion and/or tissue invasion. Most have been tested in rodents, and have been evaluated in more relevant animal models like nonhuman primates (baboons), but only a few, that is GnRH antagonists, have been tested in human randomized controlled trials. Important safety and efficacy issues remain a concern, as steroid receptors, inflammation, adhesion, angiogenesis and tissue invasion are key factors in physiological events like ovulation, menstruation and embryo implantation.

SUMMARY

New drugs for the medical treatment of endometriosis targeting both hormonal (GnRH, estrogen and progesterone receptors) and nonhormonal pathways (inflammation, angiogenesis, adhesions, tissue invasion) are promising, but their efficacy and safety need to be established in randomized human trials before they can be used in clinical practice.

High-dose atorvastatin ameliorates the uterine microenvironment in streptozotocin-induced diabetic rats

Abstract The aim of this study was to investigate whether atorvastatin can ameliorate the uterine microenvironment in diabetes mellitus. Six non-diabetic (control) and 12 diabetic mature female Sprague-Dawley albino rats were used in this study. Diabetes was induced by intraperitoneal injections of 60 mg/kg streptozotocin, and 10 mg/kg/day of oral atorvastatin was administered for 4 weeks via orogastric tubes. The animals were euthanized, and blood samples were collected via cardiac puncture for biochemical analysis. Bilateral hysterectomy was performed for the histopathologic examination. Endometrial gland degeneration and stromal fibrosis scores concomitant with epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) immunoexpressions were analyzed. The endometrial gland degeneration scores, stromal fibrosis scores and VEGF immunoexpression was significantly lower, and the EGFR immunoexpression was significantly higher in the atorvastatin-treated diabetic rats when compared to the non-treated diabetic group, suggesting that atorvastatin ameliorates the uterine microenvironment in diabetes mellitus.

The fetal safety of statins: a systematic review and meta-analysis

Although an initial case series suggested that use of statins in pregnancy carried teratogenic risk, a recent meta-analysis of controlled observational studies has failed to corroborate this. A large number of potentially beneficial uses of statins in pregnant women have prompted a new evaluation of the risk-benefit ratio of these agents in pregnancy.

Regression of experimental endometriotic implants in a rat model with the angiotensin II receptor blocker losartan

AIM

Endometriosis is a common disease in women of reproductive age, and many different treatments have been developed, although none has provided a cure. In this study, the efficacy of losartan, an angiotensin II type 1 receptor blocker and an antiangiogenic and anti-inflammatory agent, on regression of experimental endometriotic implants in a rat model was investigated.

METHODS

Peritoneal endometriosis was surgically induced in 16 mature female Sprague-Dawley rats. The peritoneal endometriotic implant was confirmed after 28 days, and the animals were divided randomly into two groups. The control group (n = 8) was given 4 mL/day tap water by oral gavage, and the losartan group (n = 8) was given 20 mg/kg per day losartan p.o. We compared endometriotic implant size, extent and severity of adhesion, as well as plasma and peritoneal lavage fluid cytokine levels including vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-α, plasma inflammatory factor pentraxin-3 (PTX-3) and C-reactive protein (CRP) between the treatment groups.

RESULTS

Mean surface endometriotic area, histological score of implants, adhesion formation, plasma VEGF, TNF, PTX-3 and CRP levels were significantly lower in the losartan group compared with control (P < 0.05). Furthermore, the peritoneal VEGF level was lower in the losartan group than in the control group (P < 0.001), but peritoneal TNF-α was similar in both groups (P > 0.05).

CONCLUSION

Losartan suppressed the implant surface area of experimental endometriosis in rats and reduced the levels of plasma VEGF, TNF-α, PTX-3 and CRP.

Atorvastatin exerts anti-nociceptive activity and decreases serum levels of high-sensitivity C-reactive protein and tumor necrosis factor-α in a rat endometriosis model

PURPOSE

The purpose of this study was to examine the effects of atorvastatin in the treatment of experimental endometriosis.

METHODS

Endometriosis was induced in 24 female rats. 4 weeks after the procedure dimensions of the foci were recorded. Rats were divided into three groups: in Group 1 (n = 8), a daily dose of 10 mg/kg atorvastatin was given for 14 days. In the second group (n = 8), a single dose of 1 mg/kg leuprolide acetate was injected intraperitoneally. The rats in Group 3 (n = 8) were received 1 mg/kg i.p. 0.9 % NaCl. At the end of the treatment, laparotomy was performed, and the dimensions of the endometriotic foci were recorded. Biochemical, histopathological and immunohistochemical studies were performed and nociception was compared in groups.

RESULTS

Atorvastatin treatment exhibited significant analgesic activity in hot plate model (P = 0.022). The serum hs-CRP and tumor necrosis TNF-α levels were similar between the Group 2 and Group 3 (P > 0.05); however atorvastatin caused significant decrease in both serum markers. The histological and immunohistochemical scores were also found to be markedly lower in Group 1 and Group 2 (P < 0.05).

CONCLUSION

Atorvastatin treatment may have a therapeutic potential in the treatment of endometriosis through its anti-inflammatory and anti-nociceptive properties.

Red yeast rice and coenzyme Q10 as safe alternatives to surmount atorvastatin-induced myopathy in hyperlipidemic rats

Statins are the first line treatment for the management of hyperlipidemia. However, the primary adverse effect limiting their use is myopathy. This study examines the efficacy and safety of red yeast rice (RYR), a source of natural statins, as compared with atorvastatin, which is the most widely used synthetic statin. Statin interference with the endogenous synthesis of coenzyme Q10 (CoQ10) prompted the hypothesis that its deficiency may be implicated in the pathogenesis of statin-associated myopathy. Hence, the effects of combination of CoQ10 with either statin have been evaluated. Rats were rendered hyperlipidemic through feeding them a high-fat diet for 90 days, during the last 30 days of the diet they were treated daily with either atorvastatin, RYR, CoQ10, or combined regimens. Lipid profile, liver function tests, and creatine kinase were monitored after 15 and 30 days of drug treatments. Heart contents of CoQ9 and CoQ10 were assessed and histopathological examination of the liver and aortic wall was performed. RYR and CoQ10 had the advantage over atorvastatin in that they lower cholesterol without elevating creatine kinase, a hallmark of myopathy. RYR maintained normal levels of heart ubiquinones, which are essential components for energy production in muscles. In conclusion, RYR and CoQ10 may offer alternatives to overcome atorvastatin-associated myopathy.

Effect of oxytocin treatment on explant size, plasma and peritoneal levels of MCP-1, VEGF, TNF-α and histopathological parameters in a rat endometriosis model

OBJECTIVE

To determine the effects of oxytocin (OT) on surgically induced endometriosis in a rat model.

STUDY DESIGN

Twelve female Sprague-Dawley rats were included. After the implantation and establishment of autologous endometrium onto the abdominal wall peritoneum, the rats were randomly divided into two groups, treated with intramuscular oxytocin (OT group, 160μgkg/day, n=6) or isotonic NaCl solution (control group, 1mLkg/day, n=6) for 28 days. To evaluate the therapeutic effects of OT, the explant volumes were calculated and the levels of vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1, and TNF-α were measured in plasma and peritoneal fluid. Endometriotic explants were examined histologically by semiquantitative analysis.

RESULTS

After treatment, the mean endometriotic explant volume was decreased in the OT group (p=0.016). The histopathological score and VEGF immunoexpression of endometriotic explants were significantly lower in the OT group (p=0.007) than in controls (p=0.000). Inflammatory cytokine levels in plasma and peritoneal fluid were considerably decreased in the OT group. Moreover, TUNEL immunohistochemistry clearly demonstrated more apoptotic changes in the mononuclear cells of the OT group compared with controls.

CONCLUSION

We suggest that oxytocin might be considered as a potential candidate therapeutic agent for endometriosis.

An overview of the current status of clinical trials on endometriosis: issues and concerns

OBJECTIVE

To examine and compare differences, if any, between industry- and nonindustry-sponsored clinical trials on endometriosis and to evaluate the effect of prior published positive preclinical results, or lack thereof, on trial status.

DESIGN

Cross-sectional study of clinical trials on endometriosis that evaluate drugs/biologicals registered at ClinicalTrials.gov as of July 3, 2013.

SETTING

University-affiliated hospital.

PATIENT(S)

None.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Trial status, size, phase, and duration; use of comparator groups; drug classes, number of arms, targeting conditions; and presence or absence of prior positive preclinical results before the launch of the trial.

RESULT(S)

Eighty trials were identified. The trials sponsored by industry and non-industry have distinct features, differing in trial status, phase, comparator, drug classes, number of arms, trial size, and duration. The phase II/III trials are predominantly industry supported, but these trials frequently use placebo as the comparator. Trials launched without prior published preclinical results do not seem to fare well, although the presence of such studies is no guarantee for success.

CONCLUSION(S)

Questions as to whether the drug on trial is truly superior to the best available drug or of its cost-benefit profile are overlooked in most cases. There seems to be a deluge of "me-too" drugs with equivocal superiority over existing drugs and cost-benefit profiles. Because clinical trials are time-consuming, no blockbuster drug for endometriosis seems to be on the horizon yet.

Effects of simvastatin on retinoic acid system in primary human endometrial stromal cells and in a chimeric model of human endometriosis

CONTEXT

Retinoic acid (RA) may promote survival or apoptosis of cells, depending on the levels of binding proteins: apoptosis-inducing cellular RA binding protein 2 (CRABP2), and cell survival-promoting fatty acid binding protein 5 (FABP5). Increased cellular uptake of retinol and altered actions of RA related to reduced expression of CRABP2 may contribute to the development of endometriosis. Recently statins have been shown to inhibit growth of human endometrial stromal (HES) cells and to reduce the number and size of endometriotic implants in experimental models of this disorder.

OBJECTIVE

The objective of the study was to determine whether effects of simvastatin on HES cells and experimental endometriotic implants are related to the modulation of the RA system.

METHODS

Effects of simvastatin and RA on proliferation and apoptosis of HES cells were evaluated. Expression of stimulated by RA 6 (STRA6), CRABP2, and FABP5 was determined by real-time PCR and Western blotting. Effects of simvastatin were also evaluated in a nude mouse model of human endometriosis.

RESULTS

Simvastatin potentiated an inhibitory effect of RA on growth of HES cells. In HES cells, simvastatin induced expression of STRA6 and CRABP2 but not FABP5. Similarly, simvastatin treatment of nude mice bearing human endometrial xenografts led to an increased expression of CRABP2 and STRA6 proteins in ectopic lesions.

CONCLUSIONS

Simvastatin interacts with the RA system, inducing the expression of the key protein regulating the uptake of retinol (STRA6) and the expression of apoptosis-promoting CRABP2. These effects may contribute to cooperative apoptosis-inducing effects of simvastatin and RA and support the examination of these compounds in the treatment of endometriosis.

Simvastatin decreases invasiveness of human endometrial stromal cells

Recently we reported that statins, the competitive inhibitors of the key enzyme regulating the mevalonate pathway, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), decrease proliferation of human endometrial stromal (HES) cells. Furthermore, we found that simvastatin treatment reduces the number and the size of endometrial implants in a nude mouse model of endometriosis. The present study was undertaken to investigate the effect of simvastatin on HES cell invasiveness and on expression of selected genes relevant to invasiveness: matrix metalloproteinase 2 (MMP2), MMP3, tissue inhibitor of matrix metalloproteinase 2 (TIMP2), and CD44. Because statin-induced inhibition of HMGCR reduces the production of substrates for isoprenylation-geranylgeranyl pyrophosphate (GGPP) and farnesyl pyrophosphate (FPP)-the effects of GGPP and FPP were also evaluated. Simvastatin induced a concentration-dependent reduction of invasiveness of HES cells. This effect of simvastatin was abrogated by GGPP but not by FPP. Simvastatin also reduced the mRNA levels of MMP2, MMP3, and CD44, but increased TIMP2 mRNA; all these effects of simvastatin were partly or entirely reversed in the presence of GGPP. The present findings provide a novel mechanism of action of simvastatin on endometrial stroma that may explain reduction of endometriosis in animal models of this disease. Furthermore, the presently described effects of simvastatin are likely mediated, at least in part, by inhibition of geranylgeranylation.

Contraceptive effect of Uncaria tomentosa (cat's claw) in rats with experimental endometriosis

PURPOSE

Evaluate the histological changes in parenchyma's epithelial layer of the uterus and ovarian of rats with induced endometriosis, treated with Uncaria tomentosa extract.

METHODS

29 rats with experimental endometriosis, were selected and divided in three groups: The uncaria group received 32 mg/ml of Uncaria tomentosa extract, 1 ml administered daily and the placebo group received 1 ml of saline 0.9% per day, during for 14 days (both groups); the leuprolide group received leuprolide acetate 1mg/kg body weight applied single subcutaneous dose. In the 15th day of treatment the uterine horn and ovaries were removed for histopathological analysis.

RESULTS

The uncaria group presented nine samples (90%) with immature ovarian follicles, whereas the placebo group did not present any case and in the leuprolide group there were eight rats (88%) with the same change. The placebo group showed mature corpus luteum in all animals, occurring less frequent in uncaria (10%) and leuprolide (22%) groups. The uterine epithelium showed weak proliferative in nine (90%) samples of the uncaria group, in two (20%) animals in the placebo group and seven (77.8%) rats in the leuprolide group.

CONCLUSIONS

The findings suggest that Uncaria tomentosa has contraceptive effect.

Changes in the volume and histology of endometriosis foci in rats treated with copaiba oil (Copaiferalangsdorffii)

PURPOSE

The aim of this study was to analyze the changes that occur in rats with experimental endometriosis after treatment with copaiba oil.

METHODS

Experimental endometriosis was induced in rats. The experimental group received copaiba oil (Copaiferalangsdorffii) orally (0.63 mg/day), and the control group received a 0.9% sodium chloride solution orally (1 ml/100 g of body weight/day). Both groups were treated with gavage for 14 days. After this period, the animals were euthanized, and the implant volume was calculated. The autologous transplants were removed, dyed with hematoxylin-eosin, and analyzed by light microscopy.

RESULTS

The average final volumes were significantly different between the groups (p=0.007). There was a significant increase (p=0.012) between the initial and final volumes in the control group, whereas treatment with Copaiferalangsdorffii caused a marked reduction in endometrial growth over time (p=0.016). Histologically, 6/11 (55.00%) rats in the experimental group had a well-preserved epithelial layer, and 3 (45.00%) had mildly preserved epithelium. The control group had seven cases (58.30%) of well-preserved epithelial cells and five cases (41.70%) of mildly preserved epithelial cells (p>0.05).

CONCLUSION

Copaiba oil (Copaiferalangsdorffii) appears to be a promising alternative treatment for endometriosis.

New trends for the medical treatment of endometriosis

INTRODUCTION

Endometriosis is a benign sex hormone-dependent gynecological disease, characterized by the presence and growth of endometrial tissue outside the uterus; it affects 10% of women of reproductive age and is associated with infertility and pain. Treatment of endometriosis involves conservative or radical surgery, or medical therapies. The goals for endometriosis treatment may be the relief of pain and/or a successful pregnancy achievement in infertile patients. Treatment must be individualized with a multidisciplinary approach. The classical treatments carry adverse side effects and in some cases a negative impact on quality of life. New agents promise a distinct perspective in endometriosis treatment.

AREAS COVERED

The aim of this paper is to systematically review the literature evidence of new medical treatments for endometriosis, defined as pharmacological treatments not yet commonly available and currently under investigation.

EXPERT OPINION

These new medical therapies would be used associated with surgical treatment and, in the future, will render possible the association of hormone therapy with non-hormonal treatment for endometriosis.

Statins inhibit monocyte chemotactic protein 1 expression in endometriosis

Statins are potent inhibitors of the endogenous mevalonate pathway. Besides inhibiting cholesterol biosynthesis, statins may also demonstrate anti-inflammatory properties. Inflammation is implicated in the attachment and invasion of endometrial cells to the peritoneal surface and growth of ectopic endometrium by inducing proliferation and angiogenesis. In this study, the effect of statins on monocyte chemotactic protein 1 (MCP-1) expression in endometriotic implants in nude mouse model and in cultured endometriotic cells was evaluated. In mouse model, simvastatin decreased MCP-1 expression in a dose-dependent manner in endometriotic implants (P < .05). Similarly, both simvastatin and mevastatin revealed a dose-dependent inhibition of MCP-1 production in cultured endometriotic cells (P < .01). This inhibitory effect of the statins on MCP-1 production was reversed by the downstream substrates of the mevalonate pathway. Moreover, statins decreased MCP-1 messenger RNA expression in cultured endometriotic cells (P < .05). In conclusion, statins exert anti-inflammatory effect in endometriotic cells and could provide a potential treatment of endometriosis in the future.

Efeito do anti-TNF-α em implantes endometriais no peritônio de ratas

OBJETIVO: Avaliar o efeito da terapia anti-TNF-α no tratamento de implantes endometriais no peritônio de ratas. MÉTODOS: Os implantes endometrióticos foram induzidos cirurgicamente em 120 ratas Wistar-Albino. Os animais foram aleatoriamente distribuídos em 4 grupos. O grupo C (n=36) recebeu uma injeção intraperitoneal de 0,2ml de solução salina. O grupo L (n=41) recebeu uma injeção subcutânea de 1mg/kg de leuprolide. O grupo I5 (n=20) recebeu uma injeção subcutânea de 5mg/kg de anticorpo monoclonal anti-fator de necrose tumoral (TNF) a (infliximab). O grupo I10 (n=20) recebeu uma injeção subcutânea de 10mg/kg de infliximab. As ratas foram sacrificadas após 21 dias para se avaliar o tamanho dos implantes e a expressão do TNF-α. RESULTADOS: O tratamento com leuprolide promoveu uma redução absoluta na área de superfície do implante comparado com o grupo C (+14mm vs. 0mm; p=0,013) e com o grupo I10 (+14mm vs. +5mm; p=0,018). Da mesma forma, uma redução percentual da area de superfície do implante foi observada comparando o grupo L com o grupo C (+33,3% vs. 0%; p=0,005) e com o grupo I10 (+33,3% vs. +18,3%; p=0,027). O tratamento com infliximab não foi capaz de diminuir a área de superfície do implante comparado com o grupo C. A expressão de TNF-α reduziu nos grupos L, I5 e I10 comparado com o grupo C (505,6µm² vs. 660,5µm² vs. 317,2µm² vs. 2519,3µm², respectivamente; p<0,001). CONCLUSÃO: A terapia anti-TNF-α reduziu a expressão de TNF-α nos implantes endometrióticos mas não reduziu a área de superfície da lesão.

Simvastatin induces estrogen receptor-alpha expression in bone, restores bone loss, and decreases ERα expression and uterine wet weight in ovariectomized rats

We previously reported that simvastatin induces estrogen receptor-alpha (ERα) in murine bone marrow stromal cells in vitro. In this study, we investigated the effect of simvastatin on ERα expression in bone and uterus in ovariectomized (OVX) rats and evaluated bone mass, bone strength, and uterine wet weight. Three-month-old Sprague-Dawley female rats received OVX or sham operation. Six weeks later, the rats were treated orally with simvastatin (5 or 10 mg/kg/day), or intraperitoneally with 17-β-estradiol (E(2)) or a combination of simvastatin and E(2) for 6 weeks. Uterine wet weight, bone mineral density (BMD) of lumbar vertebrae, biomechanics of lumbar vertebrae, and induction of ERα expression in the bone and uterus were analyzed. The 6-week simvastatin treatment improved lumbar vertebral BMD and boosted biomechanical performance of the vertebral body compared to the OVX control, suggesting that simvastatin can treat osteoporosis caused by estrogen deficiency. More interestingly, simvastatin could increase ERα expression and synergy with estradiol in bone while antagonizing estradiol in the uterus, along with uterus atrophy and uterine wet weight decreases. In conclusion, these data suggest that simvastatin exert opposing modulatory effects on ERα expression on bone and uterus in ovariectomized rats, inducing ERα expression and synergy with estrogen to perform anabolic effects on the bones while decreasing E2 efficacy and uterine wet weight. This finding may be helpful to explain the mechanism of statin treatment in osteoporosis caused by estrogen deficiency.

In vitro modulation of peroxisome proliferator-activated receptor-gamma and its genes by C-reactive protein. Role of atorvastatin

BACKGROUND AND AIMS

C-reactive protein (CRP) serves not only as a biomarker for the risk of cardiovascular disease and underlying inflammation but also functions as an active mediator of atherosclerosis by promoting activation of endothelial cells and monocytes. Peroxisome proliferator activated receptor-gamma (PPAR-gamma) transcription factor has been recognized to regulate the expression of many genes involved in inflammation, lipid metabolism and vascular remodeling. Therefore, in the present study we tried to explore the role of CRP as a possible mediator of atherosclerosis by determining its effect on PPAR-gamma and its effector genes, i.e., liver X receptor-alpha (LXR-alpha) and matrix metalloproteinase-9 (MMP-9) in THP-1 cells.

METHODS

Semi-quantitative RT-PCR was used to determine mRNA expression.

RESULTS

CRP upregulates the expression of PPAR-gamma and LXR-alpha at lower doses (5-25 microg/mL), which were further declined at higher doses (50-100 microg/mL). However, a dose-dependent increase was observed for MMP-9 expression. Atorvastatin (10-20 microM) was able to significantly accelerate the CRP-induced expression of PPAR-gamma and LXR-alpha and attenuate MMP-9 expression.

CONCLUSIONS

For the first time we demonstrate that CRP modulates PPAR-gamma and its effector genes and reinforces the mechanistic link of CRP as a possible mediator in atherosclerosis and also advocate atorvastatin as a therapeutic modality.