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Nasser, M.

Publications and source records attributed to Nasser, M..

2 recordsLinked to original sources

Neuroprotective Effect of Combined Pomegranate and Candesartan Therapy Against Chronic Cerebral Ischemia in Rats.

BackgroundStroke remains a leading cause of mortality worldwide. Ischemic stroke, caused by arterial occlusion, induces sensorimotor deficits and memory impairments. Excessive activity of the brain angiotensin II type 1 receptor (AT1R) is associated with hypertension and cerebral ischemia. Candesartan (CN), an AT1R blocker, improves cerebrovascular blood flow. Pomegranate (Punica granatum) is rich in polyphenolic antioxidants that reduce oxidative stress and inflammation, suggesting potential neuroprotective effects in cerebral ischemia. AimThis study compared the neuroprotective effects of CN administered alone or in combination with pomegranate (POM) in a rat model of cerebral ischemia induced by chronic unilateral carotid artery ligation. MethodsCerebral ischemia was induced by ligation of the right common carotid artery (RCCA) in adult rats. Animals were randomly assigned to four groups: sham control, untreated ischemic, ischemic treated with CN, and ischemic treated with CN + POM. Sensorimotor and cognitive functions were assessed 1-15 days post-surgery using beam balance (BB), beam walking (BW), modified sticky-tape (MST), novel object recognition (NOR), and the Morris water maze (MWM) tests. ResultsRCCA ligation induced marked sensorimotor deficits and memory impairments. Both CN monotherapy and CN + POM treatment equally restored sensorimotor function to sham-control levels, as demonstrated by BB, BW, and MST tests. In contrast, CN + POM treatment showed greater efficacy than CN alone in improving short-term recognition and spatial memory, as demonstrated by NOR and MWM performance. ConclusionCN effectively reverses ischemia-induced sensorimotor deficits, whereas the addition of POM confers specific and enhanced protection against cognitive impairment, indicating distinct mechanisms underlying sensorimotor and memory recovery after cerebral ischemia.

animal behavior and cognition↗

ROR2 regulates cellular plasticity in pancreatic neoplasia and adenocarcinoma

Cellular plasticity is a hallmark of pancreatic ductal adenocarcinoma (PDAC) starting from the conversion of normal cells into precancerous lesions to the progression of carcinoma subtypes associated with aggressiveness and therapeutic response. We discovered that normal acinar cell differentiation, maintained by the transcription factor Pdx1, suppresses a broad gastric cell identity that is maintained in metaplasia, neoplasia, and the classical subtype of PDAC in mouse and human. We have identified the receptor tyrosine kinase Ror2 as marker of a gastric metaplasia (SPEM)-like identity in the pancreas. Ablation of Ror2 in a mouse model of pancreatic tumorigenesis promoted a switch to a gastric pit cell identity that largely persisted through progression to the classical subtype of PDAC. In both human and mouse pancreatic cancer, ROR2 activity continued to antagonize the gastric pit cell identity, strongly promoting an epithelial to mesenchymal transition, conferring resistance to KRAS inhibition, and vulnerability to AKT inhibition. SignificanceWe discovered the receptor tyrosine kinase ROR2 as an important regulator of cellular identity in pancreatic precancerous lesions and pancreatic cancer. ROR2 drives an aggressive PDAC phenotype and confers resistance to Kras inhibitors, suggesting that targeting ROR2 will enhance sensitivity to this new generation of targeted therapies.

cancer biology↗