Thrombin Activity in Rodent and Human Skin: Modified by Inflammation and Correlates with Innervation

Network pharmacology-based strategy to reveal Acacetin against lipopolysaccharide-induced lung injury

BACKGROUND

Acacetin, a flavonoid isolated from Agastache rugosa, exhibits diverse biological activities, such as anti-tumor, anti-inflammatory and antioxidant activities. Its role in treating Lipopolysaccharide (LPS)-induced acute lung injury (ALI) remains incompletely illuminated.

OBJECTIVE

To explore the potential molecular mechanisms of Acacetin in alleviating ALI.

MATERIALS & METHODS

The network pharmacological approach was employed to screen the target genes and pathways of Acacetin. Lung injury was analyzed by Hematoxylin-Eosin (H&E) staining. Bronchoalveolar lavage fluid, serum and lung tissues were collected to detect the levels of proinflammatory cytokines and oxidative stress markers. Immunofluorescence and RT-qPCR experiments were used to observe the expression of CD45, COX2, Ly6G, and related-target proteins. In vitro, RAW264.7 macrophages were stimulated with LPS and treated with AMPK siRNA or an AMPK inhibitor Coumpound C to verify the role of AMPK/nuclear factor erythroid 2-related factor 2 (Nrf2)/high-mobility group box 1 (HMGB1) signaling in Acacetin-mediated alleviation of ALI.

RESULTS

Network data revealed that Acacetin could regulate HMGB1, AMPK, Nrf2, and IL-6. In vivo, Acacetin reversed pathological damage and the release of inflammatory factors, and alleviated oxidative stress and immune cell infiltration in ALI development. Acacetin remarkably upregulated the expression of AMPK and Nrf2, accompanied by HMGB1 downregulation. In vitro, inhibiting AMPK reversed the effects of Acacetin in LPS-treated RAW264.7, due to inactivation of AMPK/Nrf2/HMGB1 pathway.

CONCLUSION

The combination of network pharmacology and experimental studies revealed the role of Acacetin in improving ALI via the AMPK/Nrf2/HMGB1 signaling axis, which provided new insights into the treatment of ALI with Acacetin as a candidate drug.

PARIN5, a Novel Thrombin Receptor Antagonist Modulates a Streptozotocin Mice Model for Diabetic Encephalopathy

Diabetic encephalopathy (DE) is an inflammation-associated diabetes mellitus (DM) complication. Inflammation and coagulation are linked and are both potentially modulated by inhibiting the thrombin cellular protease-activated receptor 1 (PAR1). Our aim was to study whether coagulation pathway modulation affects DE. Diabetic C57BL/6 mice were treated with PARIN5, a novel PAR1 modulator. Behavioral changes in the open field and novel object recognition tests, serum neurofilament (NfL) levels and thrombin activity in central and peripheral nervous system tissue (CNS and PNS, respectively), brain mRNA expression of tumor necrosis factor α (TNF-α), Factor X (FX), prothrombin, and PAR1 were assessed. Subtle behavioral changes were detected in diabetic mice. These were accompanied by an increase in serum NfL, an increase in central and peripheral neural tissue thrombin activity, and TNF-α, FX, and prothrombin brain intrinsic mRNA expression. Systemic treatment with PARIN5 prevented the appearance of behavioral changes, normalized serum NfL and prevented the increase in peripheral but not central thrombin activity. PARIN5 treatment prevented the elevation of both TNF-α and FX but significantly elevated prothrombin expression. PARIN5 treatment prevents behavioral and neural damage in the DE model, suggesting it for future clinical research.

LPS-Induced Coagulation and Neuronal Damage in a Mice Model Is Attenuated by Enoxaparin

Background. Due to the interactions between neuroinflammation and coagulation, the neural effects of lipopolysaccharide (LPS)-induced inflammation (1 mg/kg, intraperitoneal (IP), n = 20) and treatment with the anti-thrombotic enoxaparin (1 mg/kg, IP, 15 min, and 12 h following LPS, n = 20) were studied in C57BL/6J mice. Methods. One week after LPS injection, sensory, motor, and cognitive functions were assessed by a hot plate, rotarod, open field test (OFT), and Y-maze. Thrombin activity was measured with a fluorometric assay; hippocampal mRNA expression of coagulation and inflammation factors were measured by real-time-PCR; and serum neurofilament-light-chain (NfL), and tumor necrosis factor-α (TNF-α) were measured by a single-molecule array (Simoa) assay. Results. Reduced crossing center frequency was observed in both LPS groups in the OFT (p = 0.02), along with a minor motor deficit between controls and LPS indicated by the rotarod (p = 0.057). Increased hippocampal thrombin activity (p = 0.038) and protease-activated receptor 1 (PAR1) mRNA (p = 0.01) were measured in LPS compared to controls, but not in enoxaparin LPS-treated mice (p = 0.4, p = 0.9, respectively). Serum NfL and TNF-α levels were elevated in LPS mice (p < 0.05) and normalized by enoxaparin treatment. Conclusions. These results indicate that inflammation, coagulation, neuronal damage, and behavior are linked and may regulate each other, suggesting another pharmacological mechanism for intervention in neuroinflammation.