Prenatal exposure to inflammation produces offspring that are hypertensive in adulthood. This study explored alterations of the renin-angiotensin system (RAS) during the development of hypertension induced by prenatal exposure to lipopolysaccharide (LPS). In addition, the effects of an inhibitor of the nuclear transcription factor (NF)-jB (pyrrolidine dithiocarbamate, PDTC) on this process were assessed. Pregnant rats were randomly divided into four groups (n¼8): a control group, an LPS group, a PDTC group and an LPS+PDTC group. The rats in these groups were intraperitoneally administered vehicle, 0.79 mg kg À1 LPS, 100 mg kg À1 PDTC or LPS plus PDTC, respectively. LPS was given on the 8th, 10th and 12th days, whereas PDTC was given from the 8th to the 14th day during gestation. At various ages from day 1 to 25 weeks, plasma renin activity, plasma angiotensin II (Ang II) levels, renal function, glomerular number, mRNA expression levels of renal cortex renin and angiotensin-converting enzyme (ACE), the number of Ang II-positive cells and NF-jB activation were determined. The results showed that prenatal exposure to LPS resulted in significantly lower glomerular numbers and creatinine clearance rates and higher urinary protein and renal cortex ACE mRNA expression in adult offspring. Prenatal LPS also decreased the renal cortex renin mRNA expression and the number of Ang II-positive cells in offspring at 1 day of age, but these increased at 7, 16 and 25 weeks, whereas the plasma renin activity and Ang II concentration remained unchanged. Simultaneously, PDTC treatment markedly reversed the action of LPS. In conclusion, prenatal exposure to LPS resulted in alteration of the intrarenal RAS and renal damage in adult offspring rats. INTRODUCTIONThe effects of hypertension on the cardiovascular and renal systems are of major concern due to its morbidity and mortality. Though many efforts have been made to understand the pathophysiology of hypertension, it is still unclear because of its complexity. 1 A growing body of evidence indicates that hypertension is an inflammatory state wherein proinflammatory cytokines, such as tumor necrosis factor-a and interleukin-6, contribute to the hypertensive effect. 2-5 Angiotensin II (Ang II), the major biologically active component of the reninangiotensin system (RAS), not only induces vasoconstriction, aldosterone release and sodium reabsorption by the nephron, but is also intricately interrelated with inflammation. Furthermore, the association of Ang II and inflammation induces an amplification process that involves oxidative stress and proinflammatory transcription factors, leading to progressive vascular injury 6 and having an important role in the development of hypertension and target organ damage. 2 It has been shown in our laboratory that maternal exposure to lipopolysaccharide (LPS) results in hypertension in offspring rats. 7

Previous studies have reported on the anti-atherosclerotic effects of Panax notoginseng saponins (PNS). The aim of the present study was to explore the molecular mechanisms responsible for the anti-atherosclerotic effects of PNS and the inflammatory response. Thirty rats were randomly divided into three groups, namely a control group, a group, in which zymosan A was used to induce inflammation (Zym group) and a PNS-treated group. Rats in the three groups were administered liquid paraffin (i.p.), zymosan A (20 mg/kg, i.p., once every 3 days) or zymosan A and PNS (100 mg/kg, i.p., once daily), respectively. All animals were fed a high-fat diet for 9 weeks. At scheduled times, rats were killed, blood was collected and the aorta was removed. Pathological changes in aortas were observed using Sudan IV staining and transmission electron microscopy. Serum lipids were measured enzymatically. Whole-blood viscosity was observed at different shear rates. The expression of cardiovascular disease-specific genes was determined using GEArray (SuperArray, Frederick, MA, USA). Western blotting was used to evaluate the expression levels of nuclear factor (NF)-kappaB/p65 and its inhibitor IkappaBalpha in the aortic wall. In the present study, typical pathological changes associated with atherosclerosis in rats following induction by zymosan A were alleviated by PNS treatment. In the PNS-treated group, there was a marked reduction in total serum cholesterol, triglycerides and blood viscosity. In addition, PNS treatment significantly decreased the gene expression of some inflammatory factors, such as integrins, interleukin (IL)-18, IL-1beta and matrix metalloproteinases 2 and 9. The expression of NF-kappaB/p65 was attenuated, whereas the expression of IkappaBalpha was significantly increased, after treatment with PNS. In conclusion, it appears that PNS exerts its therapeutic effects on atherosclerosis through an anti-inflammatory action and regulation of the blood lipid profile and that an NF-kappaB signalling pathway is involved.

In a previous paper, we reported that triptolide (TP), a commonly used immunomodulator, could attenuate cardiac hypertrophy. This present study aimed to further explore the inhibition of cardiac fibrosis by TP and the possible mechanism from the perspective of the NOD-like receptor protein 3 (NLRP3) inflammasome. Hematoxylin-eosin and Masson’s staining, immunohistochemistry, and immunofluorescence were performed to observe cardiac fibrotic changes in mice and mouse cardiac fibroblasts (CFs). The Western blot, colocalization, and immunoprecipitation were applied to detect protein expression and interactions. Results suggested that TP dose-dependently inhibited cardiac fibrosis induced by isoproterenol and collagen production of CFs induced by angiotensin II. TP exhibited an antifibrotic effect via inhibiting activation of the NLRP3 inflammasome, which sequentially decreased IL-1β maturation, myeloid differentiation factor 88 (MyD88)-related phosphorylation of c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase 1/2 (ERK1/2), and TGF-β1/Smad signaling, and ultimately resulted in less collagen production. Moreover, TP showed no antifibrotic effect in Nlrp3-knockout CFs. Notably, TP inhibited the expression of NLRP3 and apoptosis-associated speck-like proteins containing a caspase recruitment domain (ASC) as well as inflammasome assembly, by interrupting the NLRP3-ASC interaction to inhibit inflammasome activation. Finally, TP indeed inhibited the NLRP3-TGFβ1-Smad pathway in vivo. Conclusively, TP was found to play a dual role in interrupting the activation of the NLRP3 inflammasome to attenuate cardiac fibrosis.

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