Leandro Martin Velez

• Doctor of Biological Sciences
• PostDoc Position at University of California, Irvine

Obesity is a major risk factor for type 2 diabetes, dyslipidemia, cardiovascular disease, and hypertension. Intriguingly, there is a subset of metabolically healthy obese (MHO) individuals who are seemingly able to maintain a healthy metabolic profile free of metabolic syndrome. The molecular underpinnings of MHO, however, are not well understood....

Background Cardiovascular disease (CVD) is the leading cause of death among patients with chronic kidney disease (CKD). Rodent models are widely used to study uremic CVD pathophysiology. We compared cardiac function parameters in male and female animals from 2 established mouse CKD models and examined associations between gut-derived uremic toxins...

Obesity is a major risk factor for type 2 diabetes, dyslipidemia, cardiovascular disease, and hypertension. Intriguingly, there is a subset of metabolically healthy obese (MHO) individuals who are seemingly able to maintain a healthy metabolic profile free of metabolic syndrome. The molecular underpinnings of MHO, however, are not well understood....

Polycystic ovary syndrome (PCOS) is a complex condition with clear genetic susceptibilities that impact the heterogeneous clinical presentation of symptoms and severity through unknown mechanisms. Chronic inflammation is linked to PCOS, but a clear cause-and-effect relationship has yet to be established. This study used an in depth systems immunolo...

Importance African Americans have a higher prevalence of Type 2 Diabetes (T2D) compared to White groups. T2D is a health disparity clinically characterized by dysregulation of lipids and chronic inflammation. However, how the relationships among biological and sociological predictors of T2D drive this disparity remains to be addressed. Objective T...

Disclosure: M. Zhou: None. I. Tamburini: None. C. Van: None. J. Molendijk: None. L.M. Velez: None. C. Nguyen: None. R. Yeo: None. C. Filho: None. A.L. Hevener: None. J. Justice: None. L.M. Sparks: None. E.E. Kershaw: None. D. Nicholas: None. M. Seldin: None. Inter-organ communication is a vital process to maintain physiologic homeostasis, and its d...

Disclosure: M. Zhou: None. I. Tamburini: None. C. Van: None. J. Molendijk: None. L.M. Velez: None. C. Nguyen: None. R. Yeo: None. C. Filho: None. A.L. Hevener: None. J. Justice: None. L.M. Sparks: None. E.E. Kershaw: None. D. Nicholas: None. M. Seldin: None. Inter-organ communication is a vital process to maintain physiologic homeostasis, and its d...

Disclosure: C. Viesi: None. Type 2 Diabetes (T2D) affects over 530 million people around the globe. Insulin resistance, encompassing tissues such as muscle, adipose, and liver, is the initial step hallmarked by hyperinsulinemia. Coupled with β-cell failure, these coordinated responses progress to T2D, becoming irreversible and medically challenging...

Disclosure: L.M. Velez: None. C. Johnson: None. I. Tamburrini: None. M. Zhou: None. C. Viesi: None. N. Ujagar: None. D. Ashbrook: None. M. Nelson: None. A. Senior: None. D. James: None. R. Williams: None. D. Nicholas: None. M. Seldin: None. Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women, with a prevalence of ∼4-20% in w...

Disclosure: N. Ujagar: None. G. De Robles: None. L.M. Velez: None. M. Seldin: None. D. Nicholas: None. The etiology behind polycystic ovary syndrome (PCOS) is elusive due to the heterogeneity of its symptoms and varying severity in patients. There are a wide variety of factors associated with PCOS, like hyperinsulinemia, hyperandrogenism, endotoxem...

Disclosure: N. Ujagar: None. G. De Robles: None. L.M. Velez: None. M. Seldin: None. D. Nicholas: None. The etiology behind polycystic ovary syndrome (PCOS) is elusive due to the heterogeneity of its symptoms and varying severity in patients. There are a wide variety of factors associated with PCOS, like hyperinsulinemia, hyperandrogenism, endotoxem...

Obesity is a major risk factor for type 2 diabetes, dyslipidemia, cardiovascular disease, and hypertension. Intriguingly, there is a subset of metabolically healthy obese (MHO) individuals who are seemingly able to maintain a healthy metabolic profile free of metabolic syndrome. The molecular underpinnings of MHO, however, are not well understood....

Obesity is a major risk factor for type 2 diabetes, dyslipidemia, cardiovascular disease, and hypertension. Intriguingly, there is a subset of metabolically healthy obese (MHO) individuals who are seemingly able to maintain a healthy metabolic profile free of metabolic syndrome. The molecular underpinnings of MHO, however, are not well understood....

Inter-organ communication is a vital process to maintain physiologic homeostasis, and its dysregulation contributes to many human diseases. Given that circulating bioactive factors are stable in serum, occur naturally, and are easily assayed from blood, they present obvious focal molecules for therapeutic intervention and biomarker development. Rec...

Introduction Female reproductive function depends on a choreographed sequence of hormonal secretion and action, where specific stresses such as inflammation exert profound disruptions. Specifically, acute LPS-induced inflammation inhibits gonadotropin production and secretion from the pituitary, thereby impacting the downstream production of sex ho...

Inter-organ communication is a vital process to maintain physiologic homeostasis, and its dysregulation contributes to many human diseases. Beginning with the discovery of insulin over a century ago, characterization of molecules responsible for signal between tissues has required careful and elegant experimentation where these observations have be...

Obesity is a major risk factor for type 2 diabetes, dyslipidemia, cardiovascular disease, and hypertension. Intriguingly, there is a subset of metabolically healthy obese (MHO) individuals who are seemingly able to maintain a healthy metabolic profile free of metabolic syndrome. The molecular underpinnings of MHO, however, are not well understood....

Disclosure: L.M. Velez: None. C. Johnson: None. I. Yoon: None. K. Aberra: None. R. Feng: None. I. Tamburini: None. N. Ujagar: None. M. Nelson: None. A. Senior: None. D. Ashbrook: None. R. Williams: None. D. Nicholas: None. M. Seldin: None. Polycystic ovary syndrome (PCOS) is one of the most common female endocrinopathies, and is frequently associat...

Disclosure: C. Garcia: None. L. Velez: None. C. Fox: None. A. Mark: None. K.M. Fisch: None. M.A. Lawson: None. A. Duleba: None. M.M. Seldin: None. D. Nicholas: None. Female reproductive function depends on a perfectly choreographed sequence of hormonal secretion and action, where specific stresses such as inflammation exert profound disruptions. Sp...

Disclosure: N. Ujagar: None. G. De Robles: None. L. Velez: None. M. Seldin: None. D. Nicholas: None. The etiology behind polycystic ovary syndrome (PCOS) is elusive due to the heterogeneity of its symptoms and varying severity in patients. There are a wide variety of factors associated with PCOS, like hyperinsulinemia, hyperandrogenism, endotoxemia...

Balance between metabolic and reproductive processes is important for survival, particularly in mammals that gestate their young. How the nervous system coordinates this balance is an active area of study. Herein, we demonstrate that somatostatin (SST) neurons of the tuberal hypothalamus alter feeding in a manner sensitive to metabolic and reproduc...

Inter-organ communication is a vital process to maintain physiologic homeostasis, and its dysregulation contributes to many human diseases. Beginning with the discovery of insulin over a century ago, characterization of molecules responsible for signal between tissues has required careful and elegant experimentation where these observations have be...

Inter-organ communication is a vital process to maintain physiologic homeostasis, and its dysregulation contributes to many human diseases. Beginning with the discovery of insulin over a century ago, characterization of molecules responsible for signal between tissues has required careful and elegant experimentation where these observations have be...

Introduction Inter-organ communication is a vital process to maintain physiologic homeostasis, and its dysregulation contributes to many human diseases. Beginning with the discovery of insulin over a century ago, characterization of molecules responsible for signal between tissues has required careful and elegant experimentation where these observa...

Trade-offs between metabolic and reproductive processes are important for survival, particularly in mammals that gestate they're young. Puberty and reproduction, as energetically taxing life stages, are often gated by metabolic availability in animals with ovaries. How the nervous system coordinates these trade-offs is an active area of study. We i...

Objective Trisomy 21 is one of the most complex genetic perturbations compatible with postnatal survival. Dosage imbalance arising from the triplication of genes on human chromosome 21 (Hsa21) affects multiple organ systems. Much of Down syndrome (DS) research, however, has focused on addressing how aneuploidy dysregulates CNS function leading to c...

An alarming rise in young onset colorectal cancer (CRC) has been reported; however, the underlying molecular mechanism remains undefined. Suspected risk factors of young onset CRC include environmental aspects, such as lifestyle and dietary factors, which are known to affect the circadian clock. We find that both genetic disruption and environmenta...

Skeletal muscle plays an integral role in coordinating physiologic homeostasis, where signaling to other tissues via myokines allows for coordination of complex processes. Here, we aimed to leverage natural genetic correlation structure of gene expression both within and across tissues to understand how muscle interacts with metabolic tissues. Spec...

Proteins secreted from skeletal muscle, termed myokines, allow muscle to impact systemic physiology and disease. Myokines play critical roles in a variety of processes, including metabolic homeostasis, exercise improvements, inflammation, cancer and cognitive functions. Despite the clear relevance of these factors in mediating a multitude of physio...

Polycystic Ovary Syndrome (PCOS) is one of the most frequent endocrinopathies, affecting 5-10% of women of reproductive age, and is characterized by the presence of ovarian cysts, oligo, or anovulation, and clinical or biochemical hyperandrogenism [1]. Metabolic abnormalities such as hyperinsulinemia, insulin resistance, cardiovascular complication...

It is known that androgen excess induces changes in fetal programming that affect several physiological pathways. Peroxisome proliferator-activated receptors (PPARs) α, δ and γ are key mediators of female reproductive functions, in particular in uterine tissues. Thus, we aimed to study the effect of prenatal hyperandrogenisation on the uterine PPAR...

Background: Peroxisome proliferator-activated receptor gamma (PPARG) is a nuclear factor that may act on the early development of ovarian follicles and on follicular steroidogenesis. However, the exact mechanism of PPARG action remains unknown. We have previously found that androgen excess alters early ovarian function and the PPARG system. The aim...

This contribution is a tribute to José Yepes on the 75th anniversary of his description of the genus Tympanoctomys, and the 90th anniversary of his admission to the Argentine Museum of Natural Sciences “Bernardino Rivadavia”. Viscacha rats are the epitome of South American rodents adapted to desert habitats, and are a true model, not only to presen...

Androgens may directly modulate early ovarian follicular development in preantral stages and androgen excess before puberty may disrupt this physiological process. Therefore, the aim of this study was to investigate the dynamics of follicular morphology and circulating androgen and estradiol levels in prepubertal Wistar rats acutely exposed to andr...

Prenatal hyperandrogenism is hypothesized as one of the main factors contributing to the development of polycystic ovary syndrome (PCOS). PCOS patients have high risk of developing fatty liver and steatosis. This study aimed to evaluate the role of prenatal hyperandrogenism in liver lipid metabolism and fatty liver development. Pregnant rats were h...

Introduction: Polycystic ovary syndrome (PCOS) is a common endocrine-reproductive disorder that affects women in their reproductive age. Prenatal hyperandrogenism is able to induce polycystic ovary syndrome (PCOS) in rats. PCOS is the commonest cause of anovulatory infertility. PCOS is not only a reproductive pathology, since it includes metabolic...

The objective of the present work was to study the ovarian function when follicular development is induced during a hyperandrogenic condition. Female rats were injected either with chorionic gonadotropin (eCG group) to induce folliculogenesis or with eCG together with dehydroepiandrosterone to induce folliculogenesis in a hyperandrogenic condition...

Introduction: Polycystic ovary syndrome (PCOS) is a common endocrine-reproductive disorder that affects women in their reproductive age. Prenatal hyperandrogenism is able to induce polycystic ovary syndrome (PCOS) in rats. PCOS is the commonest cause of anovulatory infertility. PCOS is not only a reproductive pathology, since it includes metabolic...

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder affecting women in reproductive age. Although the etiology of PCOS remains unclear, it is believed to result from genetic, environmental and behavioral interactions. Women with PCOS have higher lifetime risk for cardiovascular disease (CVR) than healthy women at th...

Fuel sensors, such as glucose, insulin or leptin, are known to be directly involved in the regulation of fertility at each level of the hypothalamic-pituitary-gonadal axis. The discovery of the peroxisome proliferator-activated receptor (PPAR) family of transcription factors has revealed the link between lipid/glucose availability and long-term met...

Objective: The present study investigates the effect of prenatal hyperandrogenization on lipid metabolism and oxidant/antioxidant balance. Design: Experimental study. Setting: Research institute. Animal(s): Pregnant Sprague Dawley rats were subcutaneously injected with 2 mg free T between days 16 and 19 of pregnancy, and controls (C) receive...

Polycystic ovary syndrome (PCOS) is one of the commonest endocrine diseases that affect women in their reproductive ages; however, the etiology of the syndrome remains unknown. A hypothesis proposes that during gestation increased exposure of androgen would induce fetal programming that may increase the risk of PCOS development during the adult lif...

Prenatal hyperandrogenism is able to induce polycystic ovary syndrome (PCOS) in rats. The aim of the present study was to establish if the levels of prenatal testosterone may determine the extent of metabolic and endocrine alterations during the adult life. Pregnant Sprague Dawley rats were prenatally injected with either 2 or 5 mg free testosteron...