ABSTRACT
Osteoarthritis (OA) is a common osteoarthropathy with chronic inflammatory pain as the core symptom in middle-aged and elderly people. LncRNA MEG3 (Maternally expressed gene 3) is involved in the development of OA via regulation of angiogenesis, which causes the activation and overexpression of transient receptor potential vanilloid type-1 (TRPV1). In this study, we investigated the mechanism of MEG3-TRPV1 signaling in chronic inflammatory pain (CIP) of rat model. Chronic inflammatory pain was modeled using subcutaneous microinjection of complete Freund's adjuvant (CFA) into the left hind paw of rats. We showed that TRPV1 mRNA and protein were significantly increased, while MEG3 mRNA was significantly decreased, in the DRG and SDH of CFA-induced rats. In addition, intrathecal injection of MEG3-overexpressing lentivirus significantly downregulated TRPV1 expression and alleviated chronic inflammatory pain in CFA-induced rats. Treatment with a TRPV1 antagonist also significantly relieved chronic inflammatory pain in CFA-induced rats. In general, our results reveal that MEG3 alleviates chronic inflammatory pain by downregulating TRPV1 expression. These findings may provide new therapeutic targets in the treatment of patients with OA.
Subject(s)
Chronic Pain , RNA, Long Noncoding , Animals , Rats , Chronic Pain/complications , Chronic Pain/genetics , Freund's Adjuvant/toxicity , Hyperalgesia/drug therapy , Inflammation/complications , Inflammation/chemically induced , RNA, Long Noncoding/genetics , RNA, Messenger/genetics , TRPV Cation Channels/genetics , TRPV Cation Channels/metabolismABSTRACT
To improve nutrient content of goat milk, we describe the construction of a vector (pBLAC) containing a hybrid goat ß -lactoglobulin (BLG) promoter/cytomegalovirus (CMV) enhancer. We also describe the generation of transgenic goats expressing rhLA by somatic cell nuclear transfer (SCNT). Of 334 one-cell stage embryos derived from three transgenic cell lines and 99 embryos derived from non-transgenic (NT) cells surgically transferred to the oviducts of 37 recipients, two recipients delivered two kids (2%) from the non-transfected line and five recipients delivered six kids (1.8%) from transgenic cell lines, three of which died within 2 days. Compared to the NT donor cells, transfection of donor cells does not negatively affect the development of nuclear transfer embryos into viable transgenic offspring. However, the clone efficiency in cell line number 1 was lower than that in numbers 2 and 3, and in the NT lines (0.9% versus 1.9% 2.4% and 2%; P < 0.05). Two transgenic cloned goats expressed rhLA in the milk at 0.1-0.9 mg/mL. The mammary gland-specific expression vector pBLAC with hybrid BLG/CMV can drive the hLA gene to express in vitro and in vivo. These data establish the basis for use of a hybrid promoter/enhancer strategy to produce rhLA transgenic goats.