Hormone-sensitive lipase deficiency affects the expression of SR-BI, LDLr, and ABCA1 receptors/transporters involved in cellular cholesterol uptake and efflux and disturbs fertility in mouse testis.

Hormone-sensitive lipase (HSL) hydrolyse acylglycerols, cholesteryl and retinyl esters. HSL is a key lipase in mice testis, as HSL deficiency results in male sterility. The present work study the effects of the deficiency and lack of HSL on the localization and expression of SR-BI, LDLr, and ABCA1 receptors/transporters involved in uptake and efflux of cholesterol in mice testis, to determine the impact of HSL gene dosage on testis morphology, lipid homeostasis and fertility. The results of this work show that the lack of HSL in mice alters testis morphology and spermatogenesis, decreasing sperm counts, sperm motility and increasing the amount of Leydig cells and lipid droplets. They also show that there are differences in the localization of HSL, SR-BI, LDLr and ABCA1 in HSL+/+, HSL+/- and HSL-/- mice. The deficiency or lack of HSL has effects on protein and mRNA expression of genes involved in lipid metabolisms in mouse testis. HSL-/- testis have augmented expression of SR-BI, LDLr, ABCA1 and LXRß, a critical sterol sensor that regulate multiple genes involved in lipid metabolism; whereas LDLr expression decreased in HSL+/- mice. Plin2, Abca1 and Ldlr mRNA levels increased; and LXRα (Nr1h3) and LXRß (Nr1h2) decreased in testis from HSL-/- compared with HSL+/+; with no differences in Scarb1. Together these data suggest that HSL deficiency or lack in mice testis induces lipid homeostasis alterations that affect the cellular localization and expression of key receptors/transporter involved in cellular cholesterol uptake and efflux (SR-BI, LDRr, ABCA1); alters normal cellular function and impact fertility.

Lack of Improvement of Sperm Characteristics in Obese Males After Obesity Surgery Despite the Beneficial Changes Observed in Reproductive Hormones.

BACKGROUND: Even though obesity surgery normalizes circulating testosterone concentrations in males with obesity-associated secondary hypogonadism, its impact on spermatogenesis remains controversial. We aimed to evaluate sperm characteristics in obese men after bariatric surgery as well as changes in reproductive hormones. METHODS: Twenty severely obese men (body mass index (BMI) ≥ 35 kg/m2) were evaluated before and 2 years after bariatric surgery. The serum was assayed for insulin, leptin, kisspeptin, and inhibin B, among other hormones. Homeostasis model assessment of insulin resistance (HOMA-IR) was estimated. We used World Health Organization reference values for sperm analysis. RESULTS: After surgery, serum total testosterone, calculated free testosterone, inhibin B, and kisspeptin increased, whereas fasting insulin, HOMA-IR, and leptin concentrations decreased. Despite these improvements, sperm volume showed a small decrease after surgery, while the rest of sperm characteristics remained mostly unchanged. Abnormal sperm concentration persisted in 60% of the patients. CONCLUSIONS: Sperm characteristics may not improve after bariatric surgery despite the beneficial changes of reproductive hormones.

Morbid obesity-related changes in the expression of lipid receptors, transporters, and HSL in human sperm.

OBJECTIVE: To study the location and expression of receptors (SR-BI/CLA-1, SR-BII, and LDLr) and transporter (ABCA1) involved in uptake and efflux of cholesterol in human spermatozoa and assess whether obesity alters its location/expression and whether this could be related to infertility. DESIGN: Observational study. SETTING: None PATIENT(S): Ten controls and 20 obese patients. INTERVENTION(S): Anthropometric parameters. Serum and semen samples were collected. MAIN OUTCOME MEASURE(S): Spermatozoon concentration, immunolocalization, and protein expression in semen. RESULTS: Spermatozoon concentration and motility was decreased in morbidly obese patients. SR-BI/CLA-1, SR-BII, LDLr, and ABCA1 are located in the spermatozoon cell membrane and the localization does not change between obese patients and controls. Control spermatozoa showed high SR-BI expression, and less expression for the rest of the receptors analyzed, indicating that SR-BI/CLA-1 is relevant in human spermatozoon cholesterol uptake/efflux. On the contrary, spermatozoa of obese patients showed less SR-BI/CLA-1 expression than controls, and more intense positive staining for SR-BII, LDLr, and ABCA1. Finally, human sperm expresses the 130- and 82-kDa hormone-sensitive lipase (HSL) isoforms. The 130-kDa isoform is expressed in the control sperm, and the expression disappears in the obese patients. CONCLUSION(S): The presence of lipid receptors/transporters and HSL in human spermatozoa suggests their role in the process of maturation/capacitation. The changes in the expression of lipid receptors/transporters and the lack of the 130-kDa HSL isoform in obese patients prevent the hydrolysis of cholesterol esters internalized by these receptors, and favor their accumulation in the cytoplasm of the spermatozoa that could contribute to lipotoxicity and infertility.

Ellagic acid protects from myelin-associated sphingolipid loss in experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE), the most common model for multiple sclerosis, is characterized by inflammatory cell infiltration into the central nervous system and demyelination. Previous studies have demonstrated that administration of some polyphenols may reduce the neurological alterations of EAE. In this work, we show that ellagic acid, a polyphenolic compound, is beneficial in EAE, most likely through stimulation of ceramide biosynthesis within the brain. EAE was induced in Lewis rats by injection of guinea-pig spinal cord tissue along with Freund's complete adjuvant containing Mycobacterium tuberculosis. Clinical signs first appeared at day 8 post-immunization and reached a peak within 3 days, coincident with reduction of myelin basic protein (MBP) in the cortex. Sphingolipids, the other major components of myelin, also decreased at the acute phase of EAE, both in the cerebral cortex and in the spinal cord. In rats receiving ellagic acid in the drinking water from 2 days before immunization, the onset of the disease was delayed and clinical signs were reduced. This amelioration of clinical signs was accompanied by sustained levels of both MBP and sphingolipid in the cortex, without apparent changes in infiltration of inflammatory CD3+ T-cells, microglial activation, or weight loss, which together suggest a neuroprotective effect of ellagic acid. Finally, in glioma and oligodendroglioma cells we demonstrate that urolithins, the ellagic acid metabolites that circulate in plasma, stimulate the synthesis of ceramide. Together these data suggest that ellagic acid consumption protects against demyelination in rats with induced EAE, likely by a mechanism involving sphingolipid synthesis.

Serum Retinol, Folic Acid, and Copper Are Associated With Sperm Abnormalities in Men With Obesity.

BACKGROUND AND OBJECTIVES: Micronutrients may influence the development and differentiation of sperm cells. The aim of this study was to assess the possible association of deficiencies in several vitamins and trace elements with sperm abnormalities in men with obesity. PARTICIPANTS AND METHODS: Thirty male patients with moderate to severe obesity and ten lean controls who gave written informed consent were included. Anthropometric parameters were recorded. Hormonal and lipid profiles were analyzed, as well as serum concentrations of zinc, copper, retinol, α-tocopherol, 25-hydroxyvitamin D, cobalamin, and folic acid. For sperm analysis, we used the reference values proposed by the World Health Organization. RESULTS: Fourteen of the thirty men (47%) presented abnormal sperm results. The most common abnormality was low motility in 33% of them, followed by low sperm concentration in 27% of the patients. Patients with abnormal sperm results showed lower serum folic acid (p = 0.005) and higher serum estradiol (p = 0.015) and copper (p = 0.033) than lean controls. The ejaculate volume inversely correlated with body mass index (BMI; r = -0.378, p = 0.016) and serum estradiol (r = -0.328, p = 0.041). Total number of sperm correlated inversely with BMI (r = -0.428, p = 0.006) and serum estradiol (r = -0.507, p = 0.001) and positively with serum folic acid (r = 0.356, p = 0.026) and retinol (r = 0.421, p = 0.009). Total motility of sperm inversely correlated with BMI (r = -0.433, p = 0.005), serum estradiol (r = -0.475, p = 0.002), and copper (r = -0.416, p = 0.012) and positively correlated with serum folic acid (r = 0.522, p = 0.001) and retinol (r = 0.350, p = 0.034). CONCLUSIONS: Sperm abnormalities in men with obesity are associated with excess body weight and micronutrient concentrations.

Prevalence of male secondary hypogonadism in moderate to severe obesity and its relationship with insulin resistance and excess body weight.

To study the prevalence of male obesity-secondary hypogonadism (MOSH) in patients with moderate to severe obesity, we performed a prospective prevalence study including 100 male patients with moderate to severe obesity at a university tertiary hospital. Total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations among others were assayed in all patients. Serum-free testosterone (FT) concentration was calculated from TT and SHBG levels. Semen analysis was conducted in 31 patients. We found a prevalence of 45% (95% CI: 35-55%) when considering decreased TT and/or FT concentrations. Serum concentrations of TT were correlated negatively with glucose (r = -0.328, p < 0.001) and insulin resistance (r = -0.261, p = 0.011). The same occurred with FT and glucose (r = -0.340, p < 0.001) and insulin resistance (r = -0.246, p = 0.016). Sixty-two percent (95% CI: 39-85%) of the patients with seminogram also presented abnormal results in semen analysis. The frequencies of low TT or low FT values were similar in patients with abnormal or normal semen analysis (p = 0.646 and p = 0.346, respectively). Ejaculate volume inversely correlated with BMI (ρ = -0.400, p = 0.029) and with excess body weight (ρ = -0.464, p = 0.010). Our data show the prevalence of MOSH in patients with moderate to severe obesity is high. Low circulating testosterone is associated with insulin resistance and low ejaculate volume with higher BMI and excess body weight. Semen analysis must be performed in these patients when considering fertility whether or not presenting low circulating testosterone.

Effects of bariatric surgery on male obesity-associated secondary hypogonadism: comparison of laparoscopic gastric bypass with restrictive procedures.

Bariatric surgery results in the complete resolution of male obesity-associated secondary hypogonadism (MOSH) in many patients. However, the effects of different bariatric surgical procedures on male sexual hormone profiles and sexual dysfunction have not been compared to date. We compared the pre- and post-operative (at least 6 months after initial surgery) sex hormone profiles of 20 severely obese men submitted to laparoscopic gastric bypass (LGB) with 15 similar patients submitted to restrictive techniques (sleeve gastrectomy in 10 and adjustable gastric banding in 5). We calculated free testosterone (FT) levels from total testosterone (TT) and sex hormone binding globulin (SHBG) concentrations. Fasting glucose and insulin levels served for homeostatic model assessment of insulin resistance (HOMAIR). MOSH was present in 25 and 16 of the 35 patients when considering TT and FT concentrations respectively, resolving after surgery in all but one of them. When considering all obese men as a whole, patients submitted to LGB or restrictive procedures did not differ in terms of excess weight loss, in the decrease of fasting glucose and insulin, HOMAIR and waist circumference, or in the increase of serum 25-hydroxyvitamin D, TT and FT levels. The improvement in TT correlated with the decrease in fasting glucose (r = -0.390, P = 0.021), insulin (r = -0.425, P = 0.015) and HOMAIR (r = -0.380, P = 0.029), and with the increase in SHBG (r = 0.692, P < 0.001). The increase in FT correlated with the decrease in fasting glucose (r = -0.360, P = 0.034). LGB and restrictive techniques are equally effective in producing a remission of MOSH.

Curcumin promotes exosomes/microvesicles secretion that attenuates lysosomal cholesterol traffic impairment.

SCOPE: Exosomes/microvesicles are originated from multivesicular bodies that allow the secretion of endolysosome components out of the cell. In the present work, we investigated the effects of curcumin, a polyphenol, on exosomes/microvesicles secretion in different cells lines, using U18666A as a model of intracellular cholesterol trafficking impairment. METHODS AND RESULTS: In both HepG2 hepatocarcinoma cells and THP-1 differentiated macrophages, treatment with curcumin affected the size and the localization of endosome/lysosomes accumulated by U18666A, and reduced the cholesterol cell content. To ascertain the mechanism, we analyzed the incubation medium. Curcumin stimulated the release of cholesterol and the lysosomal ß-hexosaminidase enzyme, as well as the exosome markers, flotillin-2 and CD63. Electron microscopy studies demonstrated the presence of small vesicles similar to exosomes/microvesicles in the secretion fluid. These vesicles harbored CD63 on their surface, indicative of their endolysosomal origin. These effects of curcumin were particularly intense in cells treated with U18666A. CONCLUSION: These findings indicate that curcumin ameliorates the U18666A-induced endolysosomal cholesterol accumulation by shuttling cholesterol and presumably other lipids out of the cell via exosomes/microvesicles secretion. This action may contribute to the potential of curcumin in the treatment of lysosomal storage diseases.

HSL-knockout mouse testis exhibits class B scavenger receptor upregulation and disrupted lipid raft microdomains.

There is a tight relationship between fertility and changes in cholesterol metabolism during spermatogenesis. In the testis, class B scavenger receptors (SR-B) SR-BI, SR-BII, and LIMP II mediate the selective uptake of cholesterol esters from HDL, which are hydrolyzed to unesterified cholesterol by hormone-sensitive lipase (HSL). HSL is critical because HSL knockout (KO) male mice are sterile. The aim of the present work was to determine the effects of the lack of HSL in testis on the expression of SR-B, lipid raft composition, and related cell signaling pathways. HSL-KO mouse testis presented altered spermatogenesis associated with decreased sperm counts, sperm motility, and infertility. In wild-type (WT) testis, HSL is expressed in elongated spermatids; SR-BI, in Leydig cells and spermatids; SR-BII, in spermatocytes and spermatids but not in Leydig cells; and LIMP II, in Sertoli and Leydig cells. HSL knockout male mice have increased expression of class B scavenger receptors, disrupted caveolin-1 localization in lipid raft plasma membrane microdomains, and activated phospho-ERK, phospho-AKT, and phospho-SRC in the testis, suggesting that class B scavenger receptors are involved in cholesterol ester uptake for steroidogenesis and spermatogenesis in the testis.

Hormone-sensitive lipase expression and IHC localization in the rat ovary, oviduct, and uterus.

Hormone-sensitive lipase (HSL) is a key regulator of cholesterol esters metabolism. The aim of this study was to determine HSL localization in rat female reproductive organs during the ovarian cycle by IHC methods. HSL was located in the ovarian epithelium. The granulosa cells and oocytes of primordial follicles were immunonegative. In mature follicles, HSL was found in oocytes and theca and granulosa cells. However, HSL expression in theca cells and oocytes decreased during follicular atresia. Luteal cells showed HSL staining in cytoplasm during proestrus and estrus, in the nucleus during metestrus, and in cytoplasm and the nucleus during diestrus. In the tubaric ampulla, HSL was located in the epithelial cells nuclei and in the cilia during proestrus and estrus but mainly in the nucleus during metestrus and diestrus. In the isthmus, cells showed HSL immunolabeling in the nucleus and cilia during proestrus, but only in the cilia during estrus, metestrus, and diestrus. In the uterus, HSL was found in the epithelial cells nuclei. HSL-immunoreactive bands at 84, 67, 54, and 43 kDa were found in rat female reproductive organs. HSL labeling in the nucleus of epithelial and germ cells suggests an as yet unknown function for this protein, probably related to oogenesis and cell proliferation.

Expression, activity, and localization of hormone-sensitive lipase in rat mammary gland during pregnancy and lactation.

We examined the presence of hormone-sensitive lipase (HSL) in mammary glands of virgin, pregnant (12, 20, and 21 days), and lactating (1 and 4 days postpartum) rats. Immunohistochemistry with antibody against rat HSL revealed positive HSL in the cytoplasm of both alveolar epithelial cells and adipocytes. In virgin rats, immunoreactive HSL was observed in mammary adipocytes, whereas diffuse staining was found in the epithelial cells. Positive staining for HSL was seen in the two types of cells in pregnant and lactating rats. However, as pregnancy advanced, the staining intensity of immunoreactive HSL increased in the epithelial cells parallel to their proliferation, attaining the maximum during lactation. An immunoreactive protein of 84 kDa and a HSL mRNA of 3.3. kb were found in the rat mammary gland as in white adipose tissue. Both HSL protein and activity were lower in mammary glands from 20 and 21 day pregnant rats than from those of virgin rats, although they returned to virgin values on days 1 and 4 of lactation. Mammary gland HSL activity correlated negatively to plasma insulin levels. Immunoreactive HSL and HSL activity were found in lactating rats' milk. The observed changes indicate an active role of HSL in mammary gland lipid metabolism.

Streptozotocin-induced diabetes decreases mammary gland lipoprotein lipase activity and messenger ribonucleic acid in pregnant and nonpregnant rats.

Diabetes mellitus is associated with a reduction of lipoprotein lipase (LPL) activity in adipose tissue and development of hypertriglyceridemia. To determine how a condition of severe insulin deficiency affects mammary gland LPL activity and mRNA expression during late pregnancy, streptozotocin (STZ) treated (40 mg/kg) and non-treated (control) virgin and 20 day pregnant rats were studied. In control rats, both LPL activity and mRNA were higher in pregnant than in virgin rats. When compared to control rats, STZ-treated rats, either pregnant or virgin, showed decreased LPL activity and mRNA content. Furthermore, mammary gland LPL activity was linearly correlated with mRNA content, and either variable was linearly correlated with plasma insulin levels. Thus, insulin deficiency impairs the expression of LPL in mammary glands, revealing the role of insulin as a modulator of the enzyme at the mRNA expression level.