Intrauterine and postnatal zinc restriction may result in an adverse environment for the development of cardiovascular and renal systems. This study evaluated the effects of moderate zinc deficiency during fetal life, lactation, and/or postweaning growth on systolic blood pressure, renal function, and morphology in adult life. Female Wistar rats received low (8 ppm) or control (30 ppm) zinc diets from the beginning of pregnancy up to weaning. After weaning, male offspring of each group of mothers were fed low or control zinc diet. Systolic blood pressure, creatinine clearance, proteinuria, renal morphology, renal apoptosis. and renal oxidative stress state were evaluated after 60 days. Zinc deficiency during pre- and postweaning growth induced an increase in systolic blood pressure and a decrease in the glomerular filtration rate associated with a reduction in the number and size of nephrons. Activation of renal apoptosis, reduction in catalase activity, glutathione peroxidase activity, and glutathione levels and increase in lipid peroxidation end products could explain these morphometric changes. Zinc deficiency through pre- and postweaning growth induced more pronounced renal alteration than postweaning zinc deficiency. These animals showed signs of renal fibrosis, proteinuria, increased renal apoptosis, and higher lipid peroxidation end products. A control diet during postweaning growth did not totally overcome renal oxidative stress damage, apoptosis, and fibrosis induced by zinc deficiency before weaning. In conclusion, zinc deficiency during a critical period of renal development and maturation could induce functional and morphological alterations that result in elevated blood pressure and renal dysfunction in adult life.

We had previously shown that prenatal exposure to Zn-deficient diets induces an increase in blood pressure and impairs renal function in adult rats. The aim of the present study was to investigate if moderate Zn restriction during early growth periods, fetal life and lactation would induce impairment in the vascular and renal NO system and alterations in plasma lipid profile. We also investigated if these effects persisted into adult life, even when a Zn-replete diet was provided after weaning. Pregnant rats were fed control (30 parts per million (ppm)) or low (8 ppm) Zn diets throughout gestation up to weaning. Afterwards, male offspring from low-Zn mothers were assigned to low-or control-Zn diets during 60 d. Male offspring from control mothers were fed a control diet. Animals exposed to Zn restriction showed low birth weight, increased systolic blood pressure and serum TAG levels, and decreased glomerular filtration rate in adulthood. Zn restriction induced a decrease in vascular and renal NO synthase activity and a reduced expression of the endothelial NO synthase isoform in aorta. A control-Zn diet during post-weaning growth returned TAG levels to normal but was unsuccessful in normalising systolic blood pressure, glomerular filtration rate or NO system activity in Zn-deficient offspring. Zn restriction during fetal life, lactation and/or post-weaning growth induced alterations in the vascular and renal NO system and in lipid metabolism that could contribute to the programming of hypertension and renal dysfunction in adulthood.Arterial blood pressure: Nitric oxide system: Moderate zinc restriction: Fetal life Human epidemiological and experimental studies have provided considerable evidence to suggest that nutritional imbalance and metabolic disturbances during critical developmental time windows have persistent effects on the health of the offspring and may be responsible for in utero programming of common disorders such as obesity, diabetes and hypertension in adult life (1 -3) . Moderate and marginal Zn deficiency observed in pregnant women could be a nutritional insult to fetal and postnatal development (4,5) . Moreover, this micronutrient could program adult pathologies by an epigenetic mechanism since it controls methylation reactions and epigenetic modifications of DNA and histones (6,7) .Zn is found in a wide variety of foods such as whole-grain cereals, legumes, meat, chicken and fish. However, moderate Zn deficiency is mostly due to nutritional imbalances in those stages of life when Zn requirements are increased, such as postnatal growth and pregnancy (5,8) .We had previously reported that moderate Zn restriction during fetal life, lactation and/or post-weaning growth of rats induces an increase in arterial blood pressure (BP) and impairs renal function in adult life. These alterations were associated with an increase in renal oxidative stress, activation of renal apoptosis and fibrosis, and a reduction in the renal filtration surface area (9) . Moreover, we also reported that animals exposed to...

There is an increasing interest in the involvement of trace elements such as zinc in the pathogenesis of cardiovascular diseases. This study was designed to examine whether moderate zinc deficiency during growth influences blood pressure (BP) and vascular nitric oxide (NO) pathway. Three-week-old weaned male Wistar rats were randomly divided into two dietary groups and fed either a moderately zinc-deficient diet (zinc content 9 mg/kg; n ϭ 12) or a control diet (zinc content 30 mg/kg; n ϭ 12) for 60 d. The following were measured: systolic BP, nitrates and nitrites urinary excretion, urinary chemiluminescence intensity, NADPH-diaphorase activity in the thoracic aorta and intestinal arterioles, and NO synthase (NOS) catalytic activity using L-[U14C]-arginine as substrate in the thoracic aorta. Zinc deficiency during growth induced an increase in BP from day 30 of the experimental period, leading to hypertension on day 60. Animals that were fed the zinc-deficient diet had lower urinary excretion levels of nitrates and nitrites and higher intensity of spontaneous luminescence on day 60. At the end of the experiment, zinc-deficient rats showed decreased NADPH diaphorase activity in endothelium and smooth muscle of the thoracic aorta and intestinal arterioles and decreased activity of NOS in thoracic aortic tissue. An imbalance in zinc bioavailability during postnatal and growing periods may be may be a risk factor in development of cardiovascular alterations in adult life. The mechanisms involved may include an impaired vascular NO system as a result of decreased NOS activity and higher systemic oxidative stress. Moderate and marginal zinc deficiency is by far more common than severe deficiency, especially in infants, children, and pregnant women in developing and developed countries, as a result of imbalances between intake and increased requirements (1,2). Zinc is an essential trace element required by all living organisms for many physiologic functions, including growth, development, and reproduction (3). Zinc has been documented to act as an antioxidant, to have membranestabilizing properties, to block apoptotic cell death, and to be essential for endothelial integrity (4 -6). Intracellular zinc is associated with proteins, primarily via complex interactions with cysteines, acting as an integral component of numerous metalloenzymes, structural proteins, and transcription factors (1,7).There is increasing interest in possible involvement of trace elements such as zinc in the pathogenesis of cardiovascular diseases (8). Many enzymes that are involved in the regulation of arterial blood pressure (BP), such as nitric oxide (NO) synthase (NOS), angiotensin-converting enzyme, and neutral endopeptidases, contain zinc in their structure (9 -11). The NOSs are a family of enzymes that catalyze the synthesis of NO and L-citrulline from L-arginine in the presence of NADPH and O 2 . The NOS family consists of three isoforms that are expressed in many tissues, including endothelium and vascular

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