Second messengers mediating high-molecular-weight hyaluronan-induced antihyperalgesia in rats with chemotherapy-induced peripheral neuropathy

Exploring the Role of RhoA/ROCK Signaling in Pain: A Narrative Review

Despite significant progress in understanding the mechanisms of pain and developing therapeutic agents, pain remains a challenging and unresolved clinical issue. The Ras homolog gene family member A (RhoA), a member of the small guanosine triphosphate hydrolases (GTPases) of the Ras homolog family, is involved in transmitting signals that regulate various cellular processes. RhoA exerts its effects through a range of downstream effectors, with Rho-associated kinase (ROCK) being the most extensively studied. Emerging evidence suggests that the RhoA/ROCK signaling pathway plays a crucial role in pain transmission and sensitization. Our work indicates that targeting the RhoA/ROCK signaling pathway may offer a promising therapeutic avenue for alleviating pain.

G-protein-coupled estrogen receptor 30 regulation of signaling downstream of protein kinase Cε mediates sex dimorphism in hyaluronan-induced antihyperalgesia

ABSTRACT

High molecular weight hyaluronan (HMWH) inhibits hyperalgesia induced by diverse pronociceptive inflammatory mediators and their second messengers, in rats of both sexes. However, the hyperalgesia induced by ligands at 3 pattern recognition receptors, lipopolysaccharide (a toll-like receptor 4 agonist), lipoteichoic acid (a toll-like receptor 2/6 agonist), and nigericin (a NOD-like receptor family, pyrin domain containing 3 activator), and oxaliplatin and paclitaxel chemotherapy-induced peripheral neuropathy are only attenuated in males. After gonadectomy or intrathecal administration of an antisense to G-protein-coupled estrogen receptor 30 (GPER) mRNA, HMWH produces antihyperalgesia in females. In nociceptors cultured from rats that had been treated with oxaliplatin, HMWH reverses nociceptor sensitization from male and GPER antisense-treated female, but not from gonad intact females. G-protein-coupled estrogen receptor-dependent sex dimorphism for HMWH-induced antihyperalgesia was also observed for the prolongation of prostaglandin E 2 (PGE 2 )-induced hyperalgesia in primed nociceptors. While in primed rats, HMWH inhibits early, protein kinase A-dependent hyperalgesia, 30 minutes post PGE 2 injection, in both sexes; measured 4 hours post-PGE 2 , HMWH inhibits the protein kinase Cε (PKCε)-dependent prolongation of PGE 2 hyperalgesia only in males and GPER antisense-treated females. In females, hyperalgesia induced by PKCε agonist, ψεRACK, in control but not in primed nociceptors, was inhibited by HMWH. Inhibitors of 2 GPER second messengers, extracellular-regulated kinase 1/2 and nonreceptor tyrosine kinase, also unmasked HMWH antihyperalgesia in females with oxaliplatin chemotherapy-induced peripheral neuropathy, a condition in which nociceptors are primed as well as sensitized. Our results support GPER-dependent sex dimorphism in HMWH-induced antihyperalgesia for pain induced by pattern recognition receptor agonists, and chronic inflammatory and neuropathic pain, mediated by changes in signaling downstream of PKCε in primed nociceptors.

Endocytosis-mediated healing: recombinant human collagen type III chain-induced wound healing for scar-free recovery

Scar formation can be effectively prevented when the proportion of collagen type I (Col I)/type III (Col III) is reduced. Unlike Col III, recombinant human collagen type III chain (RHC III chain) does not possess a triple helical structure. This study aimed to elucidate the capacity of fibroblasts to uptake RHC III chain, reduce the Col I/Col III ratio and determine its effects on wound healing and scar. RHC III chain demonstrates qualified cell compatibility. In cell experiments, immunofluorescence and western blot (WB) analyses revealed an increase in the polyhistidine tag level, indicating that RHC III chain in internalized by these cells. Transmission electron microscopy showed increased intracellular phagocytic activity, indicating that RHC III chain enters fibroblasts by endocytosis. The immunofluorescence and WB showed that Col III synthesis enhanced, and Col I/Col III ratio reduced. However, the polyhistidine tag disappeared with time, indicating that RHC III chain degraded within cells and then synthesized into Col III. The content of newly synthesized Col III increases, but real-time fluorescence quantitative showed a decrease in Col III related gene content suggests the formation of negative feedback. However, due to the sufficient raw materials, the amount of Col III synthesis is still increasing, leading to the reduction of the ratio of type I collagen/type III collagen, which beneficial to wound healing and reduce scar hyperplasia. In animal experiments, the SD rat full-thickness skin defect model of wound suggests that RHC III chain also takes effect through endocytosis and ultimately promotes wound healing. The rabbit ear scar model suggests that RHC III chain inhibits scar proliferation by reducing the ratio of Col I/Col III. In summary, RHC III chain was endocytosed by fibroblasts to promote native Col III synthesis, as well as promote wound healing and reduce scar hyperplasia.

Human birth tissue products as a non-opioid medicine to inhibit post-surgical pain

Pain after surgery causes significant suffering. Opioid analgesics cause severe side effects and accidental death. Therefore, there is an urgent need to develop non-opioid therapies for managing post-surgical pain. Local application of Clarix Flo (FLO), a human amniotic membrane (AM) product, attenuated established post-surgical pain hypersensitivity without exhibiting known side effects of opioid use in mice. This effect was achieved through direct inhibition of nociceptive dorsal root ganglion (DRG) neurons via CD44-dependent pathways. We further purified the major matrix component, the heavy chain-hyaluronic acid/pentraxin 3 (HC-HA/PTX3) from human AM that has greater purity and water solubility than FLO. HC-HA/PTX3 replicated FLO-induced neuronal and pain inhibition. Mechanistically, HC-HA/PTX3-induced cytoskeleton rearrangements to inhibit sodium current and high-voltage activated calcium current on nociceptive DRG neurons, suggesting it is a key bioactive component mediating pain relief. Collectively, our findings highlight the potential of naturally derived biologics from human birth tissues as an effective non-opioid treatment for post-surgical pain. Moreover, we unravel the underlying neuronal mechanisms of pain inhibition induced by FLO and HC-HA/PTX3.

Human birth tissue products as a non-opioid medicine to inhibit post-surgical pain

Pain after surgery causes significant suffering. Opioid analgesics cause severe side effects and accidental death. Therefore, there is an urgent need to develop non-opioid therapies for managing post-surgical pain. Local application of Clarix Flo (FLO), a human amniotic membrane (AM) product, attenuated established post-surgical pain hypersensitivity without exhibiting known side effects of opioid use in mice. This effect was achieved through direct inhibition of nociceptive dorsal root ganglion (DRG) neurons via CD44-dependent pathways. We further purified the major matrix component, the heavy chain-hyaluronic acid/pentraxin 3 (HC-HA/PTX3) from human AM that has greater purity and water solubility than FLO. HC-HA/PTX3 replicated FLO-induced neuronal and pain inhibition. Mechanistically, HC-HA/PTX3 induced cytoskeleton rearrangements to inhibit sodium current and high-voltage activated calcium current on nociceptive neurons, suggesting it is a key bioactive component mediating pain relief. Collectively, our findings highlight the potential of naturally derived biologics from human birth tissues as an effective non-opioid treatment for post-surgical pain. Moreover, we unravel the underlying mechanisms of pain inhibition induced by FLO and HC-HA/PTX3.

Hyaluronic acid from bluefin tuna by-product: Structural analysis and pharmacological activities

The fishing and aquaculture industries generate a huge amount of waste during processing and preservation operations, especially those of tuna. Recovering these by-products is a major economic and environmental challenge for manufacturers seeking to produce new active biomolecules of interest. A new hyaluronic acid was extracted from bluefin tuna's vitreous humour to assess its antioxidant and pharmacological activities. The characterization by infrared spectroscopy (FT-IR), nuclear magnetic resonance ((1D1H) and 2D (1H COSY, 1H/13C HSQC)) and size exclusion chromatography (SEC/MALS/DRI/VD) revealed that the extracted polysaccharide was a hyaluronic acid with high uronic acid content (55.8 %) and a weight average molecular weight of 888 kDa. This polymer possesses significant anti-radical activity and ferrous chelating capacity. In addition, pharmacological evaluation of its anti-inflammatory and analgesic potential, using preclinical models, in comparison with reference drugs (Dexamethasone, diclofenac, and acetylsalicylate of lysine), revealed promising anti-inflammatory activity as well as interesting peripheral and central antinociceptive activity. Therefore, our new hyaluronic acid compound may therefore serve as a potential drug candidate for the treatment of pain sensation and inflammation of various pathological origins.

Topical coapplication of hyaluronan with transdermal drug delivery enhancers attenuates inflammatory and neuropathic pain

ABSTRACT

We have previously shown that intradermal injection of high-molecular-weight hyaluronan (500-1200 kDa) produces localized antihyperalgesia in preclinical models of inflammatory and neuropathic pain. In the present experiments, we studied the therapeutic effect of topical hyaluronan, when combined with each of 3 transdermal drug delivery enhancers (dimethyl sulfoxide [DMSO], protamine or terpene), in preclinical models of inflammatory and neuropathic pain. Topical application of 500 to 1200 kDa hyaluronan (the molecular weight range used in our previous studies employing intradermal administration), dissolved in 75% DMSO in saline, markedly reduced prostaglandin E 2 (PGE 2 ) hyperalgesia, in male and female rats. Although topical 500- to 1200-kDa hyaluronan in DMSO vehicle dose dependently, also markedly, attenuated oxaliplatin chemotherapy-and paclitaxel chemotherapy-induced painful peripheral neuropathy (CIPN) in male rats, it lacked efficacy in female rats. However, following ovariectomy or intrathecal administration of an oligodeoxynucleotide antisense to G-protein-coupled estrogen receptor (GPR30) mRNA, CIPN in female rats was now attenuated by topical hyaluronan. Although topical coadministration of 150 to 300, 300 to 500, or 1500 to 1750 kDa hyaluronan with DMSO also attenuated CIPN, a slightly lower-molecular-weight hyaluronan (70-120 kDa) did not. The topical administration of a combination of hyaluronan with 2 other transdermal drug delivery enhancers, protamine and terpene, also attenuated CIPN hyperalgesia, an effect that was more prolonged than with DMSO vehicle. Repeated administration of topical hyaluronan prolonged the duration of antihyperalgesia. Our results support the use of topical hyaluronan, combined with chemically diverse nontoxic skin penetration enhancers, to induce marked antihyperalgesia in preclinical models of inflammatory and neuropathic pain.

Action of Hyaluronic Acid as a Damage-Associated Molecular Pattern Molecule and Its Function on the Treatment of Temporomandibular Disorders

The temporomandibular joint is responsible for fundamental functions. However, mechanical overload or microtraumas can cause temporomandibular disorders (TMD). In addition to external factors, it is known that these conditions are involved in complex biological mechanisms, such as activation of the immune system, activation of the inflammatory process, and degradation of extracellular matrix (ECM) components. The ECM is a non-cellular three-dimensional macromolecular network; its most studied components is hyaluronic acid (HA). HA is naturally found in many tissues, and most of it has a high molecular weight. HA has attributed an essential role in the viscoelastic properties of the synovial fluid and other tissues. Additionally, it has been shown that HA molecules can contribute to other mechanisms in the processes of injury and healing. It has been speculated that the degradation product of high molecular weight HA in healthy tissues during injury, a low molecular weight HA, may act as damage-associated molecular patterns (DAMPs). DAMPs are multifunctional and structurally diverse molecules that play critical intracellular roles in the absence of injury or infection. However, after cellular damage or stress, these molecules promote the activation of the immune response. Fragments from the degradation of HA can also act as immune response activators. Low molecular weight HA would have the ability to act as a pro-inflammatory marker, promoting the activation and maturation of dendritic cells, the release of pro-inflammatory cytokines such as interleukin 1 beta (IL-1β), and tumor necrosis factor α (TNF-α). It also increases the expression of chemokines and cell proliferation. Many of the pro-inflammatory effects of low molecular weight HA are attributed to its interactions with the activation of toll-like receptors (TLRs 2 and 4). In contrast, the high molecular weight HA found in healthy tissues would act as an anti-inflammatory, inhibiting cell growth and differentiation, decreasing the production of inflammatory cytokines, and reducing phagocytosis by macrophages. These anti-inflammatory effects are mainly attributed to the interaction of high-weight HA with the CD44 receptor. In this study, we review the action of the HA as a DAMP and its functions on pain control, more specifically in orofacial origin (e.g., TMD).