G protein-coupled receptor 55 existed throughout the whole intestine of rats. O-1602 or CBD selectively normalized the motility disturbances. Possible mechanisms involved systemic anti-inflammation and the regulation of myoelectrical activity of the intestine.

Objectives: The anti-inflammatory effects of O-1602 and cannabidiol (CBD), the ligands of G proteinYcoupled receptor 55 (GPR55), on experimental acute pancreatitis (AP) were investigated.Methods: Acute pancreatitis was induced in C57BL mice by intraperitoneal injection of 50 Kg/kg cerulein hourly, with a total of 6 times. Drugs (O-1602, 10 mg/kg, or CBD, 0.5 mg/kg) were given by intraperitoneal injection 2 times at 30 minutes before the first injection and immediately before the fifth cerulein injection. At 3 hours after the last injection, the blood, the lungs, and the pancreas were harvested for the pancreatic enzyme activity, myeloperoxidase activity, and pro-inflammatory cytokines measurement; and the expressions of GPR55 mRNA and protein in the pancreas were detected.Results: Cannabidiol or O-1602 treatment significantly improved the pathological changes of mice with AP and decreased the enzyme activities, IL-6 and tumor necrosis factor > levels, and the myeloperoxidase activities in plasma and in the organ tissues. G proteinYcoupled receptor 55 mRNA and protein expressed in the pancreatic tissue, and the expressions were decreased in the mice with AP, and either CBD or O-1602 attenuated these changes to a certain extent.Conclusion: Cannabidiol and O-1602 showed anti-inflammatory effects in mice with AP and improved the expression of GPR55 in the pancreatic tissue as well.

The objective of this study was to investigate the function of heat shock protein 60 (HSP60) on pancreatic tissues by applying HSP60 small interfering RNA (siRNA) to reduce HSP60 expression. Rat pancreas was isolated and pancreatic tissue snips were prepared, cultured, and stimulated with low and high concentrations of cerulein (10(-11) and 10(-5) mol/L) or lipopolysaccharide (LPS, 10 and 20 μg/mL). Before the stimulation and 1 and 4 h after the stimulation, the viability and the level of trypsinogen activation peptide (TAP) in the tissue fragments were determined and the levels of tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) in the culture supernatants were measured. Real-time PCR and Western blotting were used to evaluate the HSP60 mRNA and protein expression. After the administration of siRNA to inhibit HSP60 expression in the isolated tissues, these injury parameters were measured and compared. The pancreatic tissues in the control (mock-interfering) group showed a decreased viability to varying degrees after being stimulated with cerulein or LPS, and the levels of TAP, TNF-α, and IL-6 increased significantly (p < 0.05) in the tissues and/or in the culture supernatant. The expressions of HSP60 mRNA and protein were raised moderately after stimulating 1 h with low concentrations of cerulein or LPS, but decreased with high concentrations of the toxicants. In particular, the expression of HSP60 protein was reduced significantly (p < 0.05) when the tissues were stimulated by the two toxicants for 4 h. In contrast, the tissue fragments in which HSP60 siRNA was applied showed much lower tissue viability (p < 0.01) and higher levels of TNF-a, IL-6, and TAP (p < 0.01) in the tissues or culture supernatant after stimulating with the toxicants at the same dose and for the same time duration as compared with those of the control groups (p < 0.05). The results indicated that both cerulein and LPS can induce injuries on isolated pancreatic tissues, but the induction effects are dependent on the duration of the stimulation and on the concentrations of the toxicants. HSP60 siRNA reduces HSP60 expression and worsens the cerulein- or LPS-induced injuries on isolated pancreatic tissues, suggesting that HSP60 has a protective effect on pancreatic tissues against these toxicants.

Acute pancreatitis (AP) is an inflammatory process in which cytokines and chemokines are involved. After onset, extrapancreatic stimuli can induce the expression of cytokines in pancreatic acinar cells, thereby amplifying this inflammatory loop. To further determine the role and mechanism of irritating agents in the pathogenesis of AP, rat pancreatic tissues were stimulated with ascitic fluid (APa) and serum (APs) from rats with AP or with lipopolysaccharide (LPS). In addition, the alteration of heat shock protein 60 (HSP60) expression was evaluated. Rat pancreas was removed and meticulously snipped to fragments. The snips were cultured for up to 48 h. During this period, the tissue viability as well as amylase and TNF-alpha levels in the supernatant and the HSP60 expression in the pancreatic tissue before and after stimulation by APa, APs, and LPS were assayed time-dependently. At different time-points during the culture, the viability and the amylase activity in the pancreatic tissue remained largely stable. After stimulation with APa, APs, or LPS for 1 h, the pancreatic tissues showed some damage, and this was followed by a sharp decrease in the viability accompanied by increased levels of amylase and TNF-alpha in the culture medium 2 or 4 h after stimulation (p < 0.05). In contrast, both the HSP60 mRNA and protein levels had a relatively high expression in the freshly prepared tissue fragments (0 h). As the culturing period was extended, the expression of HSP60 mRNA decreased only slightly; at the same time, the HSP60 protein levels decreased over a prolonged culture time, significantly so from 12 through 48 h (p < 0.05). After stimulation with APs, APa, or LPS, both the expression of HSP60 mRNA and protein in the tissue fragments increased slightly at 1 h and decreased significantly thereafter at 2 and 4 h (p < 0.05). APa, APs, or LPS induce injuries on isolated pancreatic tissues, accompanied by an altered HSP60 expression pattern in a time-dependent manner.

Lupus podocytopathy is a glomerular lesion in systemic lupus erythematosus (SLE) characterized by diffuse podocyte foot process effacement (FPE) without immune complex (IC) deposition or with only mesangial IC deposition. It is rarely seen in children with SLE. A 13-year-old girl met the 2019 European League Against Rheumatism (EULAR)/ American College of Rheumatology (ACR) Classification Criteria for SLE based on positive ANA; facial rash; thrombocytopenia; proteinuria; and positive antiphospholipid (aPL) antibodies, including lupus anticoagulant (LAC), anti-β2 glycoprotein-I antibody (anti-β2GPI), and anti-cardiolipin antibody (aCL). The renal lesion was characterized by 3+ proteinuria, a 4.2 mg/mg spot (random) urine protein to creatinine ratio, and hypoalbuminemia (26.2 g/l) at the beginning of the disease. Kidney biopsy findings displayed negative immunofluorescence (IF) for immunoglobulin A (IgA), IgM, fibrinogen (Fb), C3, and C1q, except faint IgG; a normal glomerular appearance under a light microscope; and diffuse podocyte foot process effacement (FPE) in the absence of subepithelial or subendothelial deposition by electron microscopy (EM). Histopathology of the epidermis and dermis of the pinna revealed a hyaline thrombus in small vessels. The patient met the APS classification criteria based on microvascular thrombogenesis and persistently positive aPL antibodies. She responded to a combination of glucocorticoids and immunosuppressive agents. Our study reinforces the need to consider the potential cooccurrence of LP and APS. Clinicians should be aware of the potential presence of APS in patients with a diagnosis of LP presenting with NS and positivity for aPL antibodies, especially triple aPL antibodies (LCA, anti-β2GPI, and aCL).