Acupuncture inhibits NLRP3 inflammasome activation in the prefrontal cortex of a chronic stress rat model of depression

Abstract

The Nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasomedriven inflammatory response plays a key role in the pathophysiology of depression. Mounting evidence suggests that acupuncture is an effective treatment for depression. In this study, we investigated the effects of acupuncture treatment at the acupoints Baihui (GV20) and Yintang (GV29) on NLRP3 inflammasome in the prefrontal cortex (PFC) of an animal model of depression. Rats that underwent chronic unpredictable mild stress (CUMS) for 6 weeks showed depressivelike behaviors, which were confirmed by sucrose preference and locomotor activity in the open field test. The protein levels of NLRP3, apoptotic speckcontaining protein with a card (ASC), and cysteinyl aspartate specific proteinase-1 (Caspase-1) in the PFC were detected by Western blot analysis. The mRNA and protein expressions of interleukin-1β (IL-1β) and interleukin-18 (IL-18) in the PFC were measured by the real-time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Our results showed that the depressive-like behaviors in stressed rats were reversed by acupuncture treatment. Compared with control rats, the protein expression of NLRP3, ASC, and Caspase-1 and the mRNA and protein expressions of IL-1β and IL-18 in the PFC were markedly increased in CUMS rats. Acupuncture treatment significantly decreased the levels of NLRP3 inflammasome components and inflammatory cytokines in the PFC. Acupuncture treatment also reduced the number of TUNEL-positive cells in the PFC. These results suggested that acupuncture has antidepressant-like effects, and its mechanism appears to be involved in the inhibition of NLRP3 inflammasome activation and apoptosis in the PFC.

Mechanism Underlying Acupuncture Therapy in Spinal Cord Injury: A Narrative Overview of Preclinical Studies

“…The family of NOD-like receptors (NLRs) is a vital member of the inflammasome, with NLRP3 being the most studied inflammasome in central nervous system disorders. The ability of acupuncture to attenuate the inflammatory response through inflammasome regulation, especially NLRP3, has been explored in many neurological diseases, including autism ( Zhao et al, 2022 ), postoperative cognitive dysfunction ( Sun et al, 2021 ), depression ( Li et al, 2021 ), Alzheimer’s disease ( Jiang et al, 2018 ; Zhang et al, 2021 ), cerebral ischemia ( Jiang et al, 2019 ), and vascular dementia ( Du et al, 2018 ). Further research is needed to explore the role of the inflammasome, including NLRs, in acupuncture-induced beneficial effects against SCI.…”

Electroacupuncture Alleviates Depressive-like Behavior by Modulating the Expression of P2X7/NLRP3/IL-1β of Prefrontal Cortex and Liver in Rats Exposed to Chronic Unpredictable Mild Stress

“…The rats were lightly restrained by hand to minimize stress during EA treatment. Acupuncture needles were inserted bilaterally at the Baihui (GV20), Yintang (GV29), and Ganshu (BL18) acupoints [ 43 , 44 ] to a depth of 5 mm. EA treatment caused slightly visible muscle twitching around the area of insertion.…”

Electroacupuncture alleviated depression‐like behaviors in ventromedial prefrontal cortex of chronic unpredictable mild stress‐induced rats: Increasing synaptic transmission and phosphorylating dopamine transporter

“…Rats in the EA and SSRI + EA group received EA stimulation on GV20 (at the midpoint between the auricular apices) and GV29 (at the midpoint between the medial ends of the two eyebrows). 34,35 Disposable acupuncture needles (0.16 mm × 13 mm; Hwato Appliance Factory) were inserted into both acupoints horizontally to 5 mm depth toward the tip of nose. Following the insertions, the needles were connected to electrodes for electrical stimulation with continuous waves (2 Hz in frequency, and 1 mA in intensity).…”