Yu-Ju Lin

Maternal Melatonin Therapy Rescues Prenatal Dexamethasone and Postnatal High-Fat Diet Induced Programmed Hypertension in Male Rat Offspring

Prenatal dexamethasone (DEX) exposure and high-fat (HF) intake are linked to hypertension. We examined whether maternal melatonin therapy prevents programmed hypertension synergistically induced by prenatal DEX plus postnatal HF in adult offspring. We also examined whether DEX and melatonin causes renal programming using next-generation RNA sequencing (NGS) technology. Pregnant Sprague-Dawley rats received intraperitoneal dexamethasone (0.1 mg/kg) or vehicle from gestational day 16 to 22. In the melatonin-treatment groups (M), rats received 0.01% melatonin in drinking water during their entire pregnancy and lactation. Male offspring were assigned to five groups: control, DEX, HF, DEX+HF, and DEX+HF+M. Male offspring in the HF group were fed a HF diet from weaning to 4 months of age. Prenatal DEX and postnatal HF diet synergistically induced programmed hypertension in adult offspring, which melatonin prevented. Maternal melatonin treatment modified over 3000 renal transcripts in the developing offspring kidney. Our NGS data indicate that PPAR signaling and fatty acid metabolism are two significantly regulated pathways. In addition, maternal melatonin therapy elicits longstanding alterations on renal programming, including regulation of the melatonin signaling pathway and upregulation of Agtr1b and Mas1 expression in the renin-angiotensin system (RAS), to protect male offspring against programmed hypertension. Postnatal HF aggravates prenatal DEX induced programmed hypertension in adult offspring, which melatonin prevented. The protective effects of melatonin on programmed hypertension is associated with regulation of the RAS and melatonin receptors. The long-term effects of maternal melatonin therapy on renal transcriptome require further clarification.

Resveratrol prevents the combined maternal plus postweaning high-fat-diets-induced hypertension in male offspring☆

Maternal high-fat (HF) diet is believed to induce oxidative stress and activate nutrient-sensing signals, which increase the risk of adult offspring to develop hypertension. We investigated whether resveratrol prevents the combined maternal plus postweaning HF-diets-induced hypertension in adult male offspring, with a focus on the kidney. Female Sprague-Dawley rats received either a normal diet (ND) or HF diet (D12331, Research Diets) for 5 weeks before mating and during gestation and lactation. The male offspring were placed on either the ND or HF diet from weaning to 4 months of age, resulting in four experimental groups (maternal diet/postweaning diet; n=8-10/group): ND/ND, ND/HF, HF/ND and HF/HF. Another group of HF/HF rats (n=10) was treated with 0.5% resveratrol in drinking water between 2 and 4 months of age (HF/HF+R). Rats were killed at 4 months of age. We found that HF/HF-induced hypertension in adult offspring was prevented by resveratrol. Resveratrol mediated its protective effect on HF/HF-induced hypertension in the kidneys of male offspring by diminishing oxidative stress; reducing renal asymmetric dimethylarginine levels; mediating the renin-angiotensin system (RAS) in favor of vasodilatation; restoring nutrient-sensing pathways via increased levels of silent information regulator transcript 1 (SIRT1), AMP-activated protein kinase 2α and peroxisome proliferator-activated receptor gamma coactivator 1-α; and inducing autophagy. Our data implicated an association between oxidative stress, RAS, nitric oxide, and nutrient-sensing signals in HF/HF-induced hypertension. Resveratrol, acting as an antioxidant as well as a SIRT1 activator, might be a therapeutic approach for hypertension.

High Fat Diets Sex-Specifically Affect the Renal Transcriptome and Program Obesity, Kidney Injury, and Hypertension in the Offspring

Obesity and related disorders have increased concurrently with an increased consumption of saturated fatty acids. We examined whether post-weaning high fat (HF) diet would exacerbate offspring vulnerability to maternal HF-induced programmed hypertension and kidney disease sex-specifically, with a focus on the kidney. Next, we aimed to elucidate the gene–diet interactions that contribute to maternal HF-induced renal programming using the next generation RNA sequencing (NGS) technology. Female Sprague-Dawley rats received either a normal diet (ND) or HF diet (D12331, Research Diets) for five weeks before the delivery. The offspring of both sexes were put on either the ND or HF diet from weaning to six months of age, resulting in four groups of each sex (maternal diet/post-weaning diet; n = 5–7/group): ND/ND, ND/HF, HF/ND, and HF/HF. Post-weaning HF diet increased bodyweights of both ND/HF and HF/HF animals from three to six months only in males. Post-weaning HF diet increased systolic blood pressure in male and female offspring, irrespective of whether they were exposed to maternal HF or not. Male HF/HF offspring showed greater degrees of glomerular and tubular injury compared to the ND/ND group. Our NGS data showed that maternal HF diet significantly altered renal transcriptome with female offspring being more HF-sensitive. HF diet induced hypertension and renal injury are associated with oxidative stress, activation of renin-angiotensin system, and dysregulated sodium transporters and circadian clock. Post-weaning HF diet sex-specifically exacerbates the development of obesity, kidney injury, but not hypertension programmed by maternal HF intake. Better understanding of the sex-dependent mechanisms that underlie HF-induced renal programming will help develop a novel personalized dietary intervention to prevent obesity and related disorders.

Early postnatal treatment with soluble epoxide hydrolase inhibitor or 15-deoxy-Δ12,14-prostagandin J2 prevents prenatal dexamethasone and postnatal high saturated fat diet induced programmed hypertension in adult rat offspring

Prenatal dexamethasone (DEX) exposure, postnatal high-fat (HF) intake, and arachidonic acid pathway are closely related to hypertension. We tested whether a soluble epoxide hydrolase (SEH) inhibitor, 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA) or 15-deoxy-Δ(12,14)-prostagandin J2 (15dPGJ2) therapy can rescue programmed hypertension in the DEX+HF two-hit model. Four groups of Sprague Dawley rats were studied: control, DEX+HF, AUDA, and 15dPGJ2. Dexamethasone (0.1mg/kg body weight) was intraperitoneally administered to pregnant rats from gestational day 16-22. Male offspring received high-fat diet (D12331, Research Diets) from weaning to 4 months of age. In AUDA group, mother rats received 25mg/L in drinking water during lactation. In the 15dPGJ2 group, male offspring received 15dPGJ2 1.5mg/kg BW by subcutaneous injection once daily for 1 week after birth. We found postnatal HF diet aggravated prenatal DEX-induced programmed hypertension, which was similarly prevented by early treatment with AUDA or 15dPGJ2. The beneficial effects of AUDA and 15d-PGJ2 therapy include inhibition of SEH, increases of renal angiotensin converting enzyme-2 (ACE2) and angiotensin II type 2 receptor (AT2R) protein levels, and restoration of nitric oxide bioavailability. Better understanding of the impact of arachidonic acid pathway in the two-hit model will help prevent programmed hypertension in children exposed to corticosteroids and postnatal HF intake.

N-Acetylcysteine Prevents Programmed Hypertension in Male Rat Offspring Born to Suramin-Treated Mothers.

ABSTRACT Adulthood hypertension can be programmed by preeclampsia. Preeclampsia is associated with an imbalance in vasoactive factors, including nitric oxide (NO), hydrogen sulfide (H2S), and renin-angiotensin system (RAS). We examined whether maternal N-acetylcysteine (NAC) therapy prevented maternal suramin treatment-induced programmed hypertension in offspring and explored the effects of this therapy on NO, H2S, and RAS pathways in the kidneys. Pregnant Sprague-Dawley rats were intraperitoneally administered 60 mg/kg suramin alone on Gestational Days 10 and 11 and were treated with or without 1% NAC through drinking water during the entire pregnancy and lactation period. Male offspring were divided into four groups (n = 8–10/group): control, suramin, NAC, and suramin plus NAC. All rat offspring were euthanized at 12 wk of age. Maternal suramin treatment induced programmed hypertension in male offspring, which was prevented by maternal NAC therapy. Suramin-induced programmed hypertension was associated with increased plasma asymmetric dimethylarginine (ADMA, an NO synthase inhibitor) level, decreased plasma l-arginine-to-ADMA ratio, and decreased renal dimethylarginine dimethylaminohydrolase (an ADMA-metabolizing enzyme) activity. Protective effects of NAC against suramin-induced programmed hypertension were associated with an increase in plasma glutathione level, increase in renal 3-mercaptopyruvate sulfurtransferase level, and restoration of suramin-induced reduction in H2S synthesis in the kidneys. Suramin treatment exerted negligible effect on the RAS pathway in the adult male offspring kidneys. Our data suggested interplay among suramin, ADMA-NO pathway, and H2S synthesis pathway in programmed hypertension. Furthermore, NAC administration in pregnant rats with hypertension prevented programmed hypertension in adult offspring.

Sex differences in renal transcriptome and programmed hypertension in offspring exposed to prenatal dexamethasone.

Glucocorticoids, predominantly dexamethasone (DEX), are widely used to reduce the risk of prematurity-related chronic lung disease. However, prenatal DEX treatment links to adverse effects in later life, including hypertension. Given that sex differences exist in the blood pressure (BP) control, and that renal transcriptome is sex-specific, thus we intended to elucidate whether prenatal DEX-induced programmed hypertension is in a sex-specific manner and identify candidate genes and pathways using the whole-genome RNA next-generation sequencing (NGS) approach. Offspring were assigned to 4 groups (n=7-8/group): male control (MC), female control (FC), male DEX (MD), and female DEX (FD). Dexamethasone (0.1mg/kg body weight) or vehicle was intraperitoneally administered to pregnant SD rats from gestational day 16-22, to construct a DEX model. Rats were killed at 16weeks of age. Prenatal DEX induced sex-specific increase in BPs in male but not female adult offspring. Prenatal DEX elicited renal programming in a sex-specific fashion as demonstrated by 8 and 18 DEGs in male and female offspring, respectively. Among them, two genes, Hbb and Hba-a2, were shared. The resistance of female offspring to prenatal DEX-induced programmed hypertension is related to a lower Agt expression. Prenatal DEX induced programmed hypertension in adult male but not female offspring, which was related to renal programming affecting sex-biased genes and the RAS. Early identification of sex-specific underlying mechanisms could provide novel deprogramming strategy to reach maximal optimization in both sexes.

Early Postweaning Treatment with Dimethyl Fumarate Prevents Prenatal Dexamethasone- and Postnatal High-Fat Diet-Induced Programmed Hypertension in Male Rat Offspring

Prenatal dexamethasone (DEX) exposure, postnatal high-fat (HF) intake, and oxidative stress are closely related to the development of hypertension. Nuclear factor erythroid-derived 2-related factor 2 (Nrf2) regulates oxidative stress. Dimethyl fumarate (DMF) reportedly activates Nrf2 and protects against oxidative stress damage. We examined a 4-month-old male rat offspring from five groups (n = 8 for each group): control, DEX (0.1 mg/kg i.p. from a gestational age of 16 to 22 days), HF (D12331 diet from weaning to 4 months of age), and DEX + HF, DEX + HF + DMF (50 mg/kg/day via gastric gavage for 3 weeks after weaning). We found that postnatal HF intake aggravated prenatal DEX-induced hypertension in adult male offspring, which could be prevented by DMF treatment. The beneficial effects of DMF treatment include an increase in renal Nrf2 gene expression, reduction of oxidative stress, decrease in plasma asymmetric dimethylarginine (ADMA) and renal soluble epoxide hydrolase protein levels, increase in the l-arginine-to-ADMA ratio, and activation of genes related to nutrient sensing and autophagy (e.g., Pparb, Pparg, Ppargc1a, Ulk1, and Atg5). In conclusion, better understanding of the impact of the Nrf2 signaling pathway in the two-hit model will aid in protecting children exposed to antenatal corticosteroids and a postnatal HF diet from programmed hypertension.

Maternal melatonin or agomelatine therapy prevents programmed hypertension in male offspring of mother exposed to continuous light

Abstract Hypertension can originate from early-life insults, whereas maternal melatonin therapy can be protective in a variety of models of programmed hypertension. We hypothesize that melatonin or melatonin receptor agonist agomelatine can prevent programmed hypertension in adult offspring induced by maternal exposure to continuous light. Female Sprague-Dawley pregnant rats randomly divided into four groups: controls, rats exposed to continuous light, exposed to continuous light plus treated with agomelatine (50 mg/day i.p.), and exposed to continuous light plus treated with 0.01% melatonin in drinking water throughout pregnancy and lactation period. Male offspring (n = 10/group) from three litters were examined at 12 weeks of age. Maternal continuous light exposure-induced hypertension in male offspring, which was prevented by melatonin or agomelatine therapy. Continuous light exposure did not affect melatonin pathway in adult offspring kidney. Genes that belong to the renin-angiotensin system (RAS), sodium transporters, AMP-activated protein kinase pathway, and circadian rhythm were potentially involved in the maternal exposure to continuous light-induced programmed hypertension. Maternal agomelatine therapy decreased Ace expression but increased Agtr2 and Mas1. Maternal melatonin therapy prevented the increases of Slc9a3, Slc12a3, and Atp1a1 expression induced by maternal continuous light exposure. In conclusion, maternal melatonin or agomelatine therapy prevents programmed hypertension induced by maternal exposure to continuous light. Agomelatine and melatonin reprogram the RAS and sodium transporters differentially, to prevent negative programming of continuous light. Our data highlight candidate genes and pathways in renal programming as targets for therapeutic approaches to prevent programmed hypertension caused by early-life disturbance of the circadian rhythm. Summary Sentence Exposure of the mother to continuous light-induced programmed hypertension in adult offspring, which was prevented by maternal agomelatine or melatonin therapy via regulating reninangiotensin system, sodium transporters, AMP-activated protein kinase pathway, and circadian rhythm.

A maternal high-fat diet during pregnancy and lactation, in addition to a postnatal high-fat diet, leads to metabolic syndrome with spatial learning and memory deficits: beneficial effects of resveratrol

We tested the hypothesis that high-fat diet consumption during pregnancy, lactation, and/or post weaning, altered the expression of molecular mediators involved in hippocampal synaptic efficacy and impaired spatial learning and memory in adulthood. The beneficial effect of resveratrol was assessed. Dams were fed a rat chow diet or a high-fat diet before mating, during pregnancy, and throughout lactation. Offspring were weaned onto either a rat chow or a high-fat diet. Four experimental groups were generated, namely CC, HC, CH, and HH (maternal chow diet or high-fat diet; postnatal chow diet or high-fat diet). A fifth group fed with HH plus resveratrol (HHR) was generated. Morris water maze test was used to evaluate spatial learning and memory. Blood pressure and IPGTT was measured to assess insulin resistance. Dorsal hippocampal expression of certain biochemical molecules, including sirtuin 1, ERK, PPARγ, adiponectin, and BDNF were measured. Rats in HH group showed impaired spatial memory, which was partly restored by the administration of resveratrol. Rats in HH group also showed impaired glucose tolerance and increased blood pressure, all of which was rescued by resveratrol administration. Additionally, SIRT1, phospho-ERK1/2, and phospho-PPARγ, adiponectin and BDNF were all dysregulated in rats placed in HH group; administration of resveratrol restored the expression and regulation of these molecules. Overall, our results suggest that maternal high-fat diet during pregnancy and/or lactation sensitizes the offspring to the adverse effects of a subsequent high-fat diet on hippocampal function; however, administration of resveratrol is demonstrated to be beneficial in rescuing these effects.

Combined maternal and postnatal high-fat diet leads to metabolic syndrome and is effectively reversed by resveratrol: a multiple-organ study

This study aimed to study the impact of a combination of maternal and post-weaning high-fat diets and whether resveratrol was beneficial. Sprague-Dawley dams were fed either chow or a high-fat diet, before mating, during pregnancy, and into lactation. At weaning, their offspring were randomly fed chow or a high-fat diet. Four experimental groups were generated: CC (maternal/postnatal chow diet), HC (maternal high-fat/postnatal chow diet), CH (maternal chow/postnatal high-fat diet), and HH (maternal/postnatal high-fat diet). A fifth group consisted of HH plus resveratrol. The 4 month-old offspring of HH group had higher body weight, higher levels of plasma triglycerides, leptin, angiotensin I and angiotensin II and abnormal intraperitoneal glucose tolerance test results, which fulfilled the features of metabolic syndrome. The dysregulation of the renin-angiotensin system was seen in multiple organs. Sirtuin 1 expression/abundance was reduced by a maternal/postnatal high-fat diet, in all the organs examined. Resveratrol ameliorated most of the features of metabolic syndrome and molecular alterations. The administration of a high-fat diet in both periods showed interactive metabolic effects in the plasma and many organs. Our results suggest that a maternal high-fat diet sensitizes offspring to the adverse effects of subsequent high-fat intake on multiple organs.