Methyl jasmonate regulation of pectin polysaccharides in Cosmos bipinnatus roots: A mechanistic insight into alleviating cadmium toxicity.

Methyl jasmonate (MeJA), a crucial phytohormone, which plays an important role in resistance to Cadmium (Cd) stress. The cell wall (CW) of root system is the main location of Cd and plays a key role in resistance to Cd toxicity. However, the mechanism effect of MeJA on the CW composition and Cd accumulation remain unclear. In this study, the contribution of MeJA in regulating CW structure, pectin composition and Cd accumulation was investigated in Cosmos bipinnatus. Phenotypic results affirm MeJA's significant role in reducing Cd-induced toxicity in C. bipinnatus. Notably, MeJA exerts a dual impact, reducing Cd uptake in roots while increasing Cd accumulation in the CW, particularly bound to pectin. The molecular structure of pectin, mainly uronic acid (UA), correlates positively with Cd content, consistent in HC1 and cellulose, emphasizing UA as pivotal for Cd binding. Furthermore, MeJA modulates pectin methylesterase (PME) activity under Cd stress, influencing pectin's molecular structure and homogalacturonan (HG) content affecting Cd-binding capacity. Chelate-soluble pectin (CSP) within soluble pectins accumulates a substantial Cd proportion, with MeJA regulating both UA content and the minor component 3-deoxy-oct-2-ulosonic acid (Kdo) in CSP. The study delves into the intricate regulation of pectin monosaccharide composition under Cd stress, revealing insights into the CW's physical defense and Cd binding. In summary, this research provides novel insights into MeJA-specific mechanisms alleviating Cd toxicity in C. bipinnatus, shedding light on complex interactions between MeJA, and Cd accumulation in CW pectin polysaccharide.

Fish oil alleviates liver injury induced by intestinal ischemia/reperfusion via AMPK/SIRT-1/autophagy pathway.

AIM: To evaluate whether fish oil (FO) can protect liver injury induced by intestinal ischemia/reperfusion (I/R) via the AMPK/SIRT-1/autophagy pathway. METHODS: Ischemia in Wistar rats was induced by superior mesenteric artery occlusion for 60 min and reperfusion for 240 min. One milliliter per day of FO emulsion or normal saline was administered by intraperitoneal injection for 5 consecutive days to each animal. Animals were sacrificed at the end of reperfusion. Blood and tissue samples were collected for analyses. AMPK, SIRT-1, and Beclin-1 expression was determined in lipopolysaccharide (LPS)-stimulated HepG2 cells with or without FO emulsion treatment. RESULTS: Intestinal I/R induced significant liver morphological changes and increased serum alanine aminotransferase and aspartate aminotransferase levels. Expression of p-AMPK/AMPK, SIRT-1, and autophagy markers was decreased whereas tumor necrosis factor-α (TNF-α) and malonaldehyde (MDA) were increased. FO emulsion blocked the changes of the above indicators effectively. Besides, in LPS-stimulated HepG2 cells, small interfering RNA (siRNA) targeting AMPK impaired the FO induced increase of p-AMPK, SIRT-1, and Beclin-1 and decrease of TNF-α and MDA. SIRT-1 siRNA impaired the increase of SIRT-1 and Beclin-1 and the decrease of TNF-α and MDA. CONCLUSION: Our study indicates that FO may protect the liver against intestinal I/R induced injury through the AMPK/SIRT-1/autophagy pathway.

The relation of laparotomy timing to prognosis in patients with acute necrotizing pancreatitis.

OBJECTIVE: To evaluate the relation of laparotomy timing to the prognosis in patients with acute necrotizing pancreatitis (ANP). METHODS: The laparotomy timing, morbidity, mortality and reoperation rate were reviewed in 78 patients with ANP at our hospital from 1988 to 2001. RESULTS: The morbidity rates of early operation, delayed operation and non-operation groups were 68.7%, 34.2% and 29.1%, respectively, and their mortality rates were 37.5%, 10.5% and 12.5%. The reoperation rates in early operation and delayed operation groups were 87.5% and 18.4%, respectively. CONCLUSIONS: The strategy for the management of ANP is an important factor influencing the prognosis of ANP patients. For ANP, delayed operation if necessary is more preferable than early operation in terms of better prognosis, and surgery should be simple and free from severe trauma.

Expression and role of inducible nitric oxide synthase in ischemia-reperfusion liver in rats.

OBJECTIVE: To investigate the expression and the role of iNOS expression in hepatic ischemia-reperfusion (I/R) injury. METHODS: Male Wistar rats were subjected to 30-minute hepatic ischemia, then iNOS protein and iNOS mRNA expression in liver tissue was assessed by Western blot and RT-PCR analysis respectively at different time points after reperfusion. The effects of L-NAME (Nomega-nitro-L-arginine methyl ester, a nonselective NOS inhibitor) or AE-ITU (aminoethytl-isothiourea, a relative selective inhibitor of iNOS) treatment were also evaluated. RESULTS: High levels of iNOS protein and mRNA expression were detected in the liver tissue subjected to I/R, but not in the sham-operated rats. iNOS protein and iNOS mRNA expression reached a maximum on the first day after reperfusion and decreased later. The levels of iNOS protein and iNOS mRNA disappeared on 7th, 3rd day after reperfusion respectively. The high iNOS expression was correlated with hepatic dysfunction. L-NAME administration worsened hepatic dysfunction induced by hepatic I/R. In contrast, AE-ITU administration showed mild protective effects against hepatic dysfunction induced by hepatic I/R. CONCLUSION: Ischemia-reperfusion may induce or up-regulate the expression of iNOS protein and iNOS mRNA, which is detrimental to hepatic I/R injury