Formulated Curcumin Prevents Paclitaxel-Induced Peripheral Neuropathy through Reduction in Neuroinflammation by Modulation of α7 Nicotinic Acetylcholine Receptors

Abstract

Paclitaxel is widely used in the treatment of various types of solid malignancies. Paclitaxel-induced peripheral neuropathy (PIPN) is often characterized by burning pain, cold, and mechanical allodynia in patients. Currently, specific pharmacological treatments against PIPN are lacking. Curcumin, a polyphenol of Curcuma longa, shows antioxidant, anti-inflammatory, and neuroprotective effects and has recently shown efficacy in the mitigation of various peripheral neuropathies. Here, we tested, for the first time, the therapeutic effect of 1.5% dietary curcumin and Meriva (a lecithin formulation of curcumin) in preventing the development of PIPN in C57BL/6J mice. Curcumin or Meriva treatment was initiated one week before injection of paclitaxel and continued throughout the study (21 days). Mechanical and cold sensitivity as well as locomotion/motivation were tested by the von Frey, acetone, and wheel-running tests, respectively. Additionally, sensory-nerve-action-potential (SNAP) amplitude by caudal-nerve electrical stimulation, electronic microscopy of the sciatic nerve, and inflammatory-protein quantification in DRG and the spinal cord were measured. Interestingly, a higher concentration of curcumin was observed in the spinal cord with the Meriva diet than the curcumin diet. Our results showed that paclitaxel-induced mechanical hypersensitivity was partially prevented by the curcumin diet but completely prevented by Meriva. Both the urcumin diet and the Meriva diet completely prevented cold hypersensitivity, the reduction in SNAP amplitude and reduced mitochondrial pathology in sciatic nerves observed in paclitaxel-treated mice. Paclitaxel-induced inflammation in the spinal cord was also prevented by the Meriva diet. In addition, an increase in α7 nAChRs mRNA, known for its anti-inflammatory effects, was also observed in the spinal cord with the Meriva diet in paclitaxel-treated mice. The use of the α7 nAChR antagonist and α7 nAChR KO mice showed, for the first time in vivo, that the anti-inflammatory effects of curcumin in peripheral neuropathy were mediated by these receptors. The results presented in this study represent an important advance in the understanding of the mechanism of action of curcumin in vivo. Taken together, our results show the therapeutic potential of curcumin in preventing the development of PIPN and further confirms the role of α7 nAChRs in the anti-inflammatory effects of curcumin.

Neuroprotective Effect of Natural Compounds in Paclitaxel-Induced Chronic Inflammatory Pain

“…Herbal ingredients have been studied extensively for their ability to reduce paclitaxel-induced pain. Natural treatments such as curcumin [ 9 ], resveratrol [ 10 ], gallic acid [ 11 ], puerarin [ 12 ], and naringin [ 13 ] have been shown to reduce paclitaxel-induced discomfort. Chemically, berbamine (BBM) is a bisbenzylisoquinoline alkaloid obtained from the Chinese medicinal plant Berberis amurensis Rupr .…”

Melatonin Relieves Paclitaxel-Induced Neuropathic Pain by Regulating pNEK2-Dependent Epigenetic Pathways in DRG Neurons

“…Additionally, MLT receptors exist in the central nervous system and throughout the body. Therefore, it is essential to recognize that MLT is pharmacologically active and should not be regarded as a benign agent, especially in cases of overdose. , In summary, while melatonin is generally regarded as safe when used appropriately, it is important to respect recommended dosages and consult with a health care provider before starting any new supplement regimen. Understanding individual variability and potential interactions with other medications and conditions is key to ensuring the safe and effective use of melatonin …”

“…Understanding individual variability and potential interactions with other medications and conditions is key to ensuring the safe and effective use of melatonin. 42 As a chemotherapeutic drug, PTX has also been shown to cause reproductive toxicity, thus affecting male fertility. 43 A single dose of PTX can significantly induce rat testicular changes with decreased sperm motility.…”

Research progress of traditional Chinese medicine monomer in treating diabetic peripheral neuropathy: A review

“…Modern studies have confirmed that it can inhibit the expression levels of ROS, nitric oxide (NO), protein kinase C (PKC), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, interleukin (IL)-6, NF-κB, etc, which indicates that it can play an antioxidant and anti-inflammatory role to protect peripheral nerves from damage. [10][11][12] Curcumin inhibits astrocyte proliferation, microglial activation, and neuronal apoptosis by regulating Nrf2/HO-1 and NF-kB signaling pathways. [13,14] Sang et al [15,16] showed that it can also stimulate nerve growth factor (NGF) by regulating TrkA and PI3K/Akt signaling pathway, regulates autophagy-related cells, and promote myelin regeneration and axon regeneration, suggesting that curcumin can prevent Schwann cell apoptosis through autophagy, promote NGF, and promote myelination to accelerate the repair of rat sciatic nerve injury.…”