Exercise-induced increase in M2 macrophages accelerates wound healing in young mice

Geriatric Nutritional Risk Index and Postoperative Outcomes Following Head and Neck Cancer Surgery

BACKGROUND

The geriatric nutritional risk index (GNRI) is a tool to assess preoperative nutritional status that can be calculated simply based on height, weight, and serum albumin. This study assesses the utility of GNRI in predicting postoperative complications in patients undergoing major head and neck cancer (HNC) surgery.

METHODS

Retrospective review of the 2016-2020 National Surgical Quality Improvement Program database. Patients were categorized into GNRI > 98 (normal nutritional status), GNRI 92-98 (moderate malnutrition status), and GNRI < 92 (severe malnutrition status). Univariable and multivariable binary logistic regression analyses were performed.

RESULTS

Sixteen thousand seven hundred eight-nine patients undergoing HNC resection were included. On multivariable analysis, moderate and severe malnourishment based on GNRI remained significantly associated with any surgical complication, any medical complication, any complication, Clavien-Dindo grade IV complications, and 30-day mortality.

CONCLUSIONS

GNRI may have utility as a potentially modifiable preoperative prognostic factor that can be optimized to improve complications and mortality following HNC resection.

LEVEL OF EVIDENCE

Level 4.

Omega-3 Fatty Acids and Exercise in Obesity Management: Independent and Synergistic Benefits in Metabolism and Knowledge Gaps

Obesity is a significant global health issue, profoundly affecting metabolic and cardiovascular health and other related chronic conditions. In Chile, the prevalence of obesity is among the highest within the Organisation for Economic Cooperation and Development (OECD) countries, highlighting a critical public health challenge. This narrative review examines current evidence on the independent and potential synergistic roles of omega-3 fatty acids and exercise in managing obesity-related metabolic dysfunction. Omega-3 fatty acids, particularly eicosapentaenoic acid (EPA), have been shown to lower triglyceride levels, enhance lipid metabolism, and modulate inflammation via pathways involving peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding protein-1c (SREBP-1c). Exercise interventions, such as moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT), provide distinct yet complementary metabolic benefits. Specifically, MICT improves body fat distribution and mitochondrial efficiency, whereas HIIT has notable effects on metabolic adaptability and insulin signaling. Additionally, emerging evidence points toward a potential role of the kinin-kallikrein system, particularly kallikrein 7 (KLK7), in obesity-associated insulin resistance. Despite these promising findings, several knowledge gaps persist regarding optimal dosing, intervention timing, population-specific effects, and the exact mechanisms behind the potential synergistic interactions between omega-3 supplementation and structured exercise. This review emphasizes the importance of conducting further research, particularly controlled clinical trials, to clarify these combined interventions' effectiveness and establish targeted therapeutic strategies tailored to individual metabolic profiles.

Optimizing a 5-factor cocktail to prepare reparative macrophages for wound healing

The treatment of nonhealing wounds, such as diabetic ulcers, remains a critical clinical challenge. Recent breakthroughs in cell therapy have shown great promise, with one primary focus on preparing cells with comprehensive reparative functions and foreseeable safety. In our previous study, we recapitulated the proregenerative and immunosuppressive functions of tumor-associated macrophages in non-tumor-derived macrophages, endowing the latter with characteristics for promoting diabetic wound healing-termed tumor-associated macrophage-educated macrophages. To eliminate the use of tumor-derived sources and devise a more controllable method to prepare tumor-associated macrophage-educated macrophage-like cells, in this study, we identify a cocktail comprising 5 recombinant proteins as an essential condition to induce nonpolarized macrophages into therapeutic cells with prohealing functions. The screened 5 factors are osteopontin, macrophage inflammatory protein 2, chemokine (C-C motif) ligand 8, vascular endothelial growth factor B, and macrophage colony-stimulating factor. We demonstrate the rationale for screening these factors and the phenotype of the 5 factor-induced tumor-associated macrophage-educated macrophage-like macrophages prepared from murine bone marrow-derived macrophages, which exhibit angiogenic and immunomodulatory effects in vitro. Then, we induce primary human monocytes from periphery blood into the 5 factor-induced tumor-associated macrophage-educated macrophage-like macrophages, which show prohealing effects in a human primary cell-based ex vivo model (T-Skin™). Our study demonstrates a simple, effective, and controllable approach to induce primary macrophages to possess repairing activities, which may provide insights for developing cell-based therapeutics for nonhealing wounds clinically.

Exerkines mitigating Alzheimer's disease progression by regulating inflammation: Focusing on macrophage/microglial NLRP3 inflammasome pathway

Recent research highlights the critical role of inflammation in accelerating amyloid beta and phosphorylated tubulin-associated protein tau cascade and Alzheimer's disease (AD) progression. Emerging evidence suggests that exercise influences AD by modulating inflammatory responses. We conducted a comprehensive search across multiple online databases. Our approach focused on previous and recent studies exploring the links among inflammation, AD, and the effects of exercise, specifically targeting research articles and books published in English. We pointed out that inflammation extends from the periphery to the central nervous system, facilitated by macrophage/microglial NLRP3 (nucleotide-binding domain, leucine rich-containing family, pyrin domain-containing protein 3) inflammasome signaling, which exacerbates classical AD mechanisms. Moreover, we provided further insights into the modulation of inflammasome signaling through exercise and exerkines, which may contribute to mitigating AD development. These insights deepen our understanding of AD mechanisms and offer the potential for identifying key therapeutic targets and biomarkers crucial for effective disease management and treatment. HIGHLIGHTS: Inflammation is potentially linked to the acceleration of classical Alzheimer's disease (AD) pathogenesis, including the pathways involving amyloid beta and phosphorylated tau, mediated by pro-inflammatory cytokines. Inflammation, initiated by the nucleotide-binding domain, leucine rich-containing family, pyrin domain-containing protein 3 (NLRP3) inflammasome signaling pathway within M1-type macrophages/microglia, may contribute to neuroinflammation and AD progression. Exercise has the potential to reduce inflammation and the development of AD by influencing NLRP3 inflammasome signaling via exerkines.

Hypoalbuminemia and Postoperative Outcomes Following Major Salivary Gland Resection

Objective

Hypoalbuminemia (HA) is a proxy for malnutrition that has been associated with postoperative complications in several surgical subspecialties. This study investigates the association between pre-operative HA and complications following major salivary gland (MSG) resection.

Methods

Patients undergoing outpatient, elective MSG resection were extracted from the 2005 to 2020 National Surgical Quality Improvement Program database. Demographics and comorbidities were compared between HA (preoperative serum albumin < 3.5 g/dL) and non-HA cohorts. To determine associations between albumin status and postoperative complications, univariate and multivariable binary logistic regression analyses were performed.

Results

A total of 5774 patients undergoing MSG resection were included, of which 321 (5.6%) had preoperative HA. HA was associated with older age on univariate analysis (65.2 vs. 60.2 years, p < 0.001). Multivariable analysis found HA to be independently associated with any surgical complication (OR 2.03, 95% CI 1.09-3.56, p = 0.019) and length of stay (LOS) ≥ 90th percentile (OR 1.58, 95% CI 1.04-2.38, p = 0.032).

Conclusion

Preoperative HA may be a poor prognostic factor associated with an increased risk of surgical complications and prolonged LOS among patients undergoing MSG resection.

Level of Evidence

4.

Macrophages on the run: Exercise balances macrophage polarization for improved health

OBJECTIVE

Exercise plays a crucial role in maintaining and improving human health. However, the precise molecular mechanisms that govern the body's response to exercise or/compared to periods of inactivity remain elusive. Current evidence appears to suggest that exercise exerts a seemingly dual influence on macrophage polarization states, inducing both pro-immune response M1 activation and cell-repair-focused M2 activation. To reconcile this apparent paradox, we leveraged a comprehensive meta-analysis of 75 diverse exercise and immobilization published datasets (7000+ samples), encompassing various exercise modalities, sampling techniques, and species.

METHODS

75 exercise and immobilization expression datasets were identified and processed for analysis. The data was analyzed using boolean relationships which uses binary gene expression relationships in order to increase the signal to noise achieved from the data, allowing for the use of comparison across such a diverse set of datasets. We utilized a boolean relationship-aided macrophage gene model [1], to model the macrophage polarization state in pre and post exercise samples in both immediate exercise and long term training.

RESULTS

Our modeling uncovered a key temporal dynamic: exercise triggers an immediate M1 surge, while long term training transitions to sustained M2 activation. These patterns were consistent across different species (human vs mouse), sampling methods (blood vs muscle biopsy), and exercise type (resistance vs endurance), and routinely showed statistically significant results. Immobilization was shown to have the opposite effect of exercise by triggering an immediate M2 activation. Individual characteristics like gender, exercise intensity and age were found to impact the degree of polarization without changing the overall patterns. To model macrophages within the specific context of muscle tissue, we identified a focused gene set signature of muscle resident macrophage polarization, allowing for the precise measurement of macrophage activity in response to exercise within the muscle.

CONCLUSIONS

These consistent patterns across all 75 examined studies suggest that the long term health benefits of exercise stem from its ability to orchestrate a balanced and temporally-regulated interplay between pro-immune response (M1) and reparative macrophage activity (M2). Similarly, it suggests that an imbalance between pro-immune and cell repair responses could facilitate disease development. Our findings shed light on the intricate molecular choreography behind exercise-induced health benefits with a particular insight on its effect on the macrophages within the muscle.

Exercise-regulated lipolysis: Its role and mechanism in health and diseases

Exercise has received considerable attention because of its importance not just in regulating physiological function, but also in ameliorating multiple pathological processes. Among these processes, lipolysis may play an important role in exercise-induced benefits. It is generally accepted that active lipolysis contributes to breakdown of fats, leading to the release of free fatty acids (FFAs) that serve as an energy source for muscles and other tissues during exercise. However, the significance of lipolysis in the context of exercise has not been fully understood. This review comprehensively outlines the potential regulatory mechanisms by which exercise stimulates lipolysis. The potential roles of exercise-mediated lipolysis in various physiological and pathological processes are also summarized. Additionally, we also discussed the potential non-classical effects of key lipolytic effectors induced by exercise. This will enhance our understanding of how exercise improves lipolytic function to bring about beneficial effects, offering new insights into potential therapeutic avenues for promoting health and alleviating diseases.

Cardiac macrophage metabolism in health and disease

Cardiac macrophages are essential mediators of cardiac development, tissue homeostasis, and response to injury. Cell-intrinsic shifts in metabolism and availability of metabolites regulate macrophage function. The human and mouse heart contain a heterogeneous compilation of cardiac macrophages that are derived from at least two distinct lineages. In this review, we detail the unique functional roles and metabolic profiles of tissue-resident and monocyte-derived cardiac macrophages during embryonic development and adult tissue homeostasis and in response to pathologic and physiologic stressors. We discuss the metabolic preferences of each macrophage lineage and how metabolism influences monocyte fate specification. Finally, we highlight the contribution of cardiac macrophages and derived metabolites on cell-cell communication, metabolic health, and disease pathogenesis.

Low-intensity pulsed ultrasound phonophoresis with diclofenac alleviated inflammation and pain via downregulation of M1 macrophages in rats with carrageenan-induced knee joint arthritis

Objective

This study aimed to investigate the effects of low-intensity pulsed ultrasound (LIPUS) phonophoresis with diclofenac on inflammation and pain in the acute phase of carrageenan-induced arthritis in rats.

Design

60 male Wistar rats were randomly divided into the arthritis, diclofenac, LIPUS, phonophoresis, and sham-arthritis control groups. LIPUS and transdermal diclofenac gel were applied to the lateral side of the inflamed knee for 7 days, initiated postinjection day 1. In the phonophoresis group, diclofenac gel was rubbed onto the skin, followed by LIPUS application over the medication. Knee joint transverse diameters, pressure pain thresholds (PPTs), and paw withdrawal thresholds (PWT) were evaluated. The number of CD68-, CD11c-, and CD206-positive cells, and IL-1β and COX-2 mRNA expression were analyzed 8 days after injection.

Results

In the phonophoresis group, the transverse diameter, PPT, PWT significantly recovered at the day 8 compared to those in the LIPUS and diclofenac groups. The number of CD68- and CD11c-positive cells in the phonophoresis group was significantly lower than that in the LIPUS and diclofenac groups, but no significant differences were observed among three groups in CD206-positive cells. IL-1β and COX-2 mRNA levels were lower in the phonophoresis group than in the arthritis group, although there were no differences among the LIPUS, diclofenac, and phonophoresis groups.

Conclusion

LIPUS phonophoresis with diclofenac is more effective to ameliorate inflammation and pain compared to diclofenac or LIPUS alone, and the mechanism involves the decrease of M1 macrophages.

Can Exercise Enhance the Efficacy of Checkpoint Inhibition by Modulating Anti-Tumor Immunity?

Immune checkpoint inhibition (ICI) has revolutionized cancer therapy. However, response to ICI is often limited to selected subsets of patients or not durable. Tumors that are non-responsive to checkpoint inhibition are characterized by low anti-tumoral immune cell infiltration and a highly immunosuppressive tumor microenvironment. Exercise is known to promote immune cell circulation and improve immunosurveillance. Results of recent studies indicate that physical activity can induce mobilization and redistribution of immune cells towards the tumor microenvironment (TME) and therefore enhance anti-tumor immunity. This suggests a favorable impact of exercise on the efficacy of ICI. Our review delivers insight into possible molecular mechanisms of the crosstalk between muscle, tumor, and immune cells. It summarizes current data on exercise-induced effects on anti-tumor immunity and ICI in mice and men. We consider preclinical and clinical study design challenges and discuss the role of cancer type, exercise frequency, intensity, time, and type (FITT) and immune sensitivity as critical factors for exercise-induced impact on cancer immunosurveillance.

Exercise therapy for chronic pain: How does exercise change the limbic brain function?

We are exposed to various external and internal threats which might hurt us. The role of taking flexible and appropriate actions against threats is played by "the limbic system" and at the heart of it there is the ventral tegmental area and nucleus accumbens (brain reward system). Pain-related fear causes excessive excitation of amygdala, which in turn causes the suppression of medial prefrontal cortex, leading to chronification of pain. Since the limbic system of chronic pain patients is functionally impaired, they are maladaptive to their situations, unable to take goal-directed behavior and are easily caught by fear-avoidance thinking. We describe the neural mechanisms how exercise activates the brain reward system and enables chronic pain patients to take goal-directed behavior and overcome fear-avoidance thinking. A key to getting out from chronic pain state is to take advantage of the behavioral switching function of the basal nucleus of amygdala. We show that exercise activates positive neurons in this nucleus which project to the nucleus accumbens and promote reward behavior. We also describe fear conditioning and extinction are affected by exercise. In chronic pain patients, the fear response to pain is enhanced and the extinction of fear memories is impaired, so it is difficult to get out of "fear-avoidance thinking". Prolonged avoidance of movement and physical inactivity exacerbate pain and have detrimental effects on the musculoskeletal and cardiovascular systems. Based on the recent findings on multiple bran networks, we propose a well-balanced exercise prescription considering the adherence and pacing of exercise practice. We conclude that therapies targeting the mesocortico-limbic system, such as exercise therapy and cognitive behavioral therapy, may become promising tools in the fight against chronic pain.

Why Does Rehabilitation Not (Always) Work in Osteoarthritis? Does Rehabilitation Need Molecular Biology?

Osteoarthritis (OA) is a common disease among the human population worldwide. OA causes functional impairment, leads to disability and poses serious socioeconomic burden. The rehabilitation offers a function-oriented method to reduce the disability using diverse interventions (kinesiotherapy, physical therapy, occupational therapy, education, and pharmacotherapy). OA as a widespread disease among elderly patients is often treated by rehabilitation specialists and physiotherapists, however the results of rehabilitation are sometimes unsatisfactory. The understanding of molecular mechanisms activated by rehabilitation may enable the development of more effective rehabilitation procedures. Molecular biology methods may prove crucial in rehabilitation as the majority of rehabilitation procedures cannot be estimated in double-blinded placebo-controlled trials commonly used in pharmacotherapy. This article attempts to present and estimate the role of molecular biology in the development of modern rehabilitation. The role of clinicians in adequate molecular biology experimental design is also described.

Microtomographic, histomorphometric, and molecular features show a normal alveolar bone healing process in iNOS-deficient mice along a compensatory upregulation of eNOS and nNOS isoforms

METHODOLOGY

Inducible nitric oxide synthase (iNOS) is one of the enzymes responsible for the synthesis of nitric oxide (NO), which is an important signaling molecule with effects on blood vessels, leukocytes, and bone cells. However, the role of iNOS in alveolar bone healing remains unclear. This study investigated the role of iNOS in alveolar bone healing after tooth extraction in mice. C57Bl/6 wild type (WT) and iNOS genetically deficient (iNOS-KO) mice were subjected to upper incision tooth extraction, and alveolar bone healing was evaluated by micro-computed tomography (μCT) and histological/histomorphometric, birefringence, and molecular methods.

RESULTS

The expression of iNOS had very low control conditions, whereas a significant increase is observed in healing sites of WT mice, where iNOS mRNA levels peak at 7d time point, followed by a relative decrease at 14d and 21d. Regarding bone healing, both WT and iNOS-KO groups showed the usual phases characterized by the presence of clots, granulation tissue development along the inflammatory cell infiltration, angiogenesis, proliferation of fibroblasts and extracellular matrix synthesis, bone neoformation, and remodeling. The overall micro-computed tomography and histomorphometric and birefringence analyses showed similar bone healing readouts when WT and iNOS-KO strains are compared. Likewise, Real-Time PCR array analysis shows an overall similar gene expression pattern (including bone formation, bone resorption, and inflammatory and immunological markers) in healing sites of WT and iNOS-KO mice. Moreover, molecular analysis shows that nNOS and eNOS were significantly upregulated in the iNOS-KO group, suggesting that other NOS isoforms could compensate the absence of iNOS.

CONCLUSION

The absence of iNOS does not result in a significant modulation of bone healing readouts in iNOS-KO mice. The upregulation of nNOS and eNOS may compensate iNOS absence, explaining the similar bone healing outcome in WT and iNOS-KO strains.