Baicalein attenuates pancreatic inflammatory injury through regulating MAPK, STAT 3 and NF-κB activation.

Acute pancreatitis (AP) is a common acute abdominal disease with local or systemic inflammatory response, caused by abnormal activation of digestive enzymes. Baicalein has been shown to exert anti-inflammatory effects and to attenuate the pathological changes of AP. The aim of the research was to investigate the effects of baicalein on caerulein induced pancreatitis, and to elucidate the putative underlying mechanism. In this study, the therapeutic potential of baicalein and its mechanism were investigated in a caerulein-induced AP in vivo and in vitro model. The results indicate that baicalein treatment alleviates the caerulein-induced pathological damage in the pancreas. Baicalein decreased the expression level of pro-inflammatory cytokines and chemokines of the pancreas in caerulein treated mice and of isolated pancreatic acinar cells. Moreover, baicalein inhibited the expression of NF-κB p65 and the phosphorylation of p38 MAPK, ERK (extracellular signal-regulated kinase) as well as STAT 3, which indicates that baicalein exerts its anti-inflammatory effects via dampening the NF-κB, MAPK and STAT 3 signaling pathways. Together, this study provides experimental evidence for the clinical application of Scutellaria baicalensis Georgi or baicalein and indicates that baicalein may be a promising candidate for treatment of AP patients in the future.

Baicalein inhibits acinar-to-ductal metaplasia of pancreatic acinal cell AR42J via improving the inflammatory microenvironment.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers. Recent research has demonstrated that chronic pancreatitis (CP) is associated with an increased risk of PDAC, partly due to acinar-to-ductal metaplasia (ADM). Baicalein has been shown to exert anti-inflammatory and anti-tumor effects for CP or PDAC, respectively. The aim of our study was to investigate the effect of baicalein, and the putative underlying mechanism, on inflammatory cytokines-induced ADM of rat pancreatic acinar cell line AR42J. To investigate ADM and baicalein effects in vitro, AR42J were treated with recombinant rat Tumor Necrosis Factor alpha (rTNFα) with or without baicalein for 5 days. Results showed that rTNFα-induced AR42J cells switched their phenotype from dominantly amylase-positive acinar cells to dominantly cytokeratin 19-positive ductal cells. Moreover, expression of the transcripts for TNFα or Hes-1, a Notch target, was up-regulated in these cells. Interestingly, baicalein reduced the population of ADM as well as cytokines gene expression but not Hes-1. Baicalein inhibited NF-κB activation induced by rTNFα in AR42J, but no effect on Notch 1activation. Moreover, baicalein suppressed the secretion of TNFα and Nitric Oxide (NO) in macrophages stimulated with LPS and further inhibited ADM of conditional medium-treated AR42J cells. Baicalein also suppressed the inflammatory response of LPS-activated macrophages, thereby inhibited ADM of AR42J by altering their microenvironment. Taken together, our study indicates that baicalein reduces rTNFα-induced ADM of AR42J cells by inhibiting NF-κB activation. It also sheds new light on Chinese material medica therapy of pancreatitis and thereby prevention of PDAC.

Targeting tumor-associated macrophages by anti-tumor Chinese materia medica.

Tumor-associated macrophages (TAMs) play a key role in all stages of tumorigenesis and tumor progression. TAMs secrete different kinds of cytokines, chemokines, and enzymes to affect the progression, metastasis, and resistance to therapy depending on their state of reprogramming. Therapeutic benefit in targeting TAMs suggests that macrophages are attractive targets for cancer treatment. Chinese materia medica (CMM) is an important approach for treating cancer in China and in the Asian region. According to the theory of Chinese medicine (CM) and its practice, some prescriptions of CM regulate the body's internal environment possibly including the remodeling the tumor microenvironment (TME). Here we briefly summarize the pivotal effects of TAMs in shaping the TME and promoting tumorigenesis, invasion, metastasis and immunosuppression. Furthermore, we illustrate the effects and mechanisms of CMM targeting TAMs in antitumor therapy. Finally, we reveal the CMM's dual-regulatory and multi-targeting functions on regulating TAMs, and hopefully, provide the theoretical basis for CMM clinical practice related to cancer therapy.