Effect of Enzogenol® Supplementation on Cognitive, Executive, and Vestibular/Balance Functioning in Chronic Phase of Concussion

Brain Mechanisms Explaining Postural Imbalance in Traumatic Brain Injury: A Systematic Review

Introduction: Persisting imbalance and falls in community-dwelling traumatic brain injury (TBI) survivors are linked to reduced long-term survival. However, a detailed understanding of the impact of TBI upon the brain mechanisms mediating imbalance is lacking. To understand the state of the art concerning the brain mechanisms mediating imbalance in TBI, we performed a systematic review of the literature. Methods: PubMed, Web of Science, and Scopus were searched and peer-reviewed research articles in humans, with any severity of TBI (mild, moderate, severe, or concussion), which linked a postural balance assessment (objective or subjective) with brain imaging (through computed tomography, T1-weighted imaging, functional magnetic resonance imaging [fMRI], resting-state fMRI, diffusion tensor imaging, magnetic resonance spectroscopy, single-photon emission computed tomography, electroencephalography, magnetoencephalography, near-infrared spectroscopy, and evoked potentials) were included. Out of 1940 articles, 60 were retrieved and screened, and 25 articles fulfilling inclusion criteria were included. Results: The most consistent finding was the link between imbalance and the cerebellum; however, the regions within the cerebellum were inconsistent. Discussion: The lack of consistent findings could reflect that imbalance in TBI is due to a widespread brain network dysfunction, as opposed to focal cortical damage. The inconsistency in the reported findings may also be attributed to heterogeneity of methodology, including data analytical techniques, small sample sizes, and choice of control groups. Future studies should include a detailed clinical phenotyping of vestibular function in TBI patients to account for the confounding effect of peripheral vestibular disorders on imbalance and brain imaging.

A Potential Role Exists for Nutritional Interventions in the Chronic Phase of Mild Traumatic Brain Injury, Concussion and Sports-Related Concussion: A Systematic Review

Mild traumatic brain injury (mTBI) represents a significant burden for individuals, economies, and healthcare systems worldwide. Recovery protocols focus on medication and physiotherapy-based interventions. Animal studies have shown that antioxidants, branched-chain amino acids and omega-3 fatty acids may improve neurophysiological outcomes after TBI. However, there appears to be a paucity of nutritional interventions in humans with chronic (≥1 month) symptomology post-mTBI. This systematic literature review aimed to consolidate evidence for nutrition and dietary-related interventions in humans with chronic mTBI. The review was registered with the International Prospective Register of Systematic Reviews (PROSPERO; CRD42021277780) and conducted following the Preferred Reporting for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three reviewers searched five databases (PubMed/MEDLINE, Web of Science, SPORTDiscus, CINAHL Complete and Cochrane), which yielded 6164 studies. Nine studies met the inclusion criteria. The main finding was the lack of interventions conducted to date, and a quality assessment of the included studies was found to be fair to good. Due to heterogeneity, a meta-analysis was not feasible. The six nutrition areas identified (omega-3 fatty acids, melatonin, Enzogenol®, MLC901, ketogenic diet and phytocannabinoids) were safe and well-tolerated. It was found that these nutritional interventions may improve cognitive failures, sleep disturbances, anxiety, physical disability, systolic blood pressure volume and sport concussion assessment tool scores following mTBI. Potential areas of improvement identified for future studies included blinding, reporting compliance, and controlling for confounders. In conclusion, further research of higher quality is needed to investigate the role of nutrition in recovery from mTBI to reduce the burden of chronic outcomes following mTBI.

Targeted interventions and their effect on recovery in children, adolescents and adults who have sustained a sport-related concussion: a systematic review

OBJECTIVES

We evaluated interventions to facilitate recovery in children, adolescents and adults with a sport-related concussion (SRC).

DESIGN

Systematic review including risk of bias (modified Scottish Intercollegiate Guidelines Network tool).

DATA SOURCES

MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Embase, APA PsycINFO, Cochrane Central Register of Controlled Trials, CINAHL Plus with Full Text, SPORTDiscus and Scopus searched until March 2022.

STUDY ELIGIBILITY CRITERIA

(1) Original research including randomised controlled trials (RCTs), quasi-experimental designs, cohort, comparative effectiveness studies; (2) focus on SRC; (3) English; (4) peer-reviewed and (5) evaluated treatment.

RESULTS

6533 studies were screened, 154 full texts reviewed and 13 met inclusion (10 RCTs, 1 quasi-experimental and 2 cohort studies; 1 high-quality study, 7 acceptable and 5 at high risk of bias). Interventions, comparisons, timing and outcomes varied, precluding meta-analysis. For adolescents and adults with dizziness, neck pain and/or headaches >10 days following concussion, individualised cervicovestibular rehabilitation may decrease time to return to sport compared with rest followed by gradual exertion (HR 3.91 (95% CI 1.34 to 11.34)) and when compared with a subtherapeutic intervention (HR 2.91 (95% CI 1.01 to 8.43)). For adolescents with vestibular symptoms/impairments, vestibular rehabilitation may decrease time to medical clearance (vestibular rehab group 50.2 days (95% CI 39.9 to 60.4) compared with control 58.4 (95% CI 41.7 to 75.3) days). For adolescents with persisting symptoms >30 days, active rehabilitation and collaborative care may decrease symptoms.

CONCLUSIONS

Cervicovestibular rehabilitation is recommended for adolescents and adults with dizziness, neck pain and/or headaches for >10 days. Vestibular rehabilitation (for adolescents with dizziness/vestibular impairments >5 days) and active rehabilitation and/or collaborative care (for adolescents with persisting symptoms >30 days) may be of benefit.

Inflammaging, cellular senescence, and cognitive aging after traumatic brain injury

Traumatic brain injury (TBI) is associated with mortality and morbidity worldwide. Accumulating pre-clinical and clinical data suggests TBI is the leading extrinsic cause of progressive neurodegeneration. Neurological deterioration after either a single moderate-severe TBI or repetitive mild TBI often resembles dementia in aged populations; however, no currently approved therapies adequately mitigate neurodegeneration. Inflammation correlates with neurodegenerative changes and cognitive dysfunction for years post-TBI, suggesting a potential association between immune activation and both age- and TBI-induced cognitive decline. Inflammaging, a chronic, low-grade sterile inflammation associated with natural aging, promotes cognitive decline. Cellular senescence and the subsequent development of a senescence associated secretory phenotype (SASP) promotes inflammaging and cognitive aging, although the functional association between senescent cells and neurodegeneration is poorly defined after TBI. In this mini-review, we provide an overview of the pre-clinical and clinical evidence linking cellular senescence with poor TBI outcomes. We also discuss the current knowledge and future potential for senotherapeutics, including senolytics and senomorphics, which kill and/or modulate senescent cells, as potential therapeutics after TBI.

Symptom Factors and Neuropsychological Performance in Collegiate Athletes with Chronic Concussion Symptoms

OBJECTIVE

The present study explored the relationship between specific types of postconcussion symptoms and cognitive outcomes in student-athletes with chronic concussion symptoms.

METHOD

Forty student-athletes with chronic concussion symptoms were given a battery of neuropsychological tests and rated themselves on a variety of postconcussion symptoms, which included the following factors derived from prior work: Physical, Sleep, Cognitive, Affective, and Headache. Cognitive outcomes included performance on composites for the memory and attention/executive functioning speed tests, respectively. The following covariates were also explored: Sex, depression symptoms, number of previous concussions, and time since injury.

RESULTS

Headache was the only individual symptom factor that significantly (p < .05) predicted worse attention/executive functioning performance. None of the symptom factors were significantly related to memory performance over and above the variable of time since injury, such that longer time since injury was related to worse memory performance.

CONCLUSION

Comparable to work examining symptom predictors of cognitive outcomes in acutely concussed samples, headache predicted worse attention/executive functioning performance. Additionally, we found that the longer athletes had been symptomatic since injury, the "worse" their memory functioning. Understanding how headache and the length of time an individual is symptomatic are related to cognitive outcomes can help inform treatment and recommendations for athletes with prolonged symptom recovery.

Natural Phytochemicals Derived from Gymnosperms in the Prevention and Treatment of Cancers

The incidence of various types of cancer is increasing globally. To reduce the critical side effects of cancer chemotherapy, naturally derived compounds have been considered for cancer treatment. Gymnosperms are a group of plants found worldwide that have traditionally been used for therapeutic applications. Paclitaxel is a commercially available anticancer drug derived from gymnosperms. Other natural compounds with anticancer activities, such as pinostrobin and pinocembrin, are extracted from pine heartwood, and pycnogenol and enzogenol from pine bark. Gymnosperms have great potential for further study for the discovery of new anticancer compounds. This review aims to provide a rational understanding and the latest developments in potential anticancer compounds derived from gymnosperms.

Nutritional interventions to improve neurophysiological impairments following traumatic brain injury: A systematic review

Traumatic brain injury (TBI) accounts for significant global health burden. Effects of TBI can become chronic even following mild injury. There is a need to develop effective therapies to attenuate the damaging effects of TBI and improve recovery outcomes. This literature review using a priori criteria (PROSPERO; CRD42018100623) summarized 43 studies between January 1998 and July 2019 that investigated nutritional interventions (NUT) delivered with the objective of altering neurophysiological (NP) outcomes following TBI. Risk of bias was assessed for included studies, and NP outcomes recorded. The systematic search resulted in 43 of 3,748 identified studies met inclusion criteria. No studies evaluated the effect of a NUT on NP outcomes of TBI in humans. Biomarkers of morphological changes and apoptosis, oxidative stress, and plasticity, neurogenesis, and neurotransmission were the most evaluated NP outcomes across the 43 studies that used 2,897 animals. The risk of bias was unclear in all reviewed studies due to poorly detailed methodology sections. Taking these limitations into account, anti-oxidants, branched chain amino acids, and ω-3 polyunsaturated fatty acids have shown the most promising pre-clinical results for altering NP outcomes following TBI. Refinement of pre-clinical methodologies used to evaluate effects of interventions on secondary damage of TBI would improve the likelihood of translation to clinical populations.

Pine bark (Pinus spp.) extract for treating chronic disorders

BACKGROUND

Pine bark (Pinus spp.) extract is rich in bioflavonoids, predominantly proanthocyanidins, which are antioxidants. Commercially-available extract supplements are marketed for preventing or treating various chronic conditions associated with oxidative stress. This is an update of a previously published review.

OBJECTIVES

To assess the efficacy and safety of pine bark extract supplements for treating chronic disorders.

SEARCH METHODS

We searched three databases and three trial registries; latest search: 30 September 2019. We contacted the manufacturers of pine bark extracts to identify additional studies and hand-searched bibliographies of included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating pine bark extract supplements in adults or children with any chronic disorder.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, extracted data and assessed risk of bias. Where possible, we pooled data in meta-analyses. We used GRADE to evaluate the certainty of evidence. Primary outcomes were participant- and investigator-reported clinical outcomes directly related to each disorder and all-cause mortality. We also assessed adverse events and biomarkers of oxidative stress.

MAIN RESULTS

This review included 27 RCTs (22 parallel and five cross-over designs; 1641 participants) evaluating pine bark extract supplements across 10 chronic disorders: asthma (two studies; 86 participants); attention deficit hyperactivity disorder (ADHD) (one study; 61 participants), cardiovascular disease (CVD) and risk factors (seven studies; 338 participants), chronic venous insufficiency (CVI) (two studies; 60 participants), diabetes mellitus (DM) (six studies; 339 participants), erectile dysfunction (three studies; 277 participants), female sexual dysfunction (one study; 83 participants), osteoarthritis (three studies; 293 participants), osteopenia (one study; 44 participants) and traumatic brain injury (one study; 60 participants). Two studies exclusively recruited children; the remainder recruited adults. Trials lasted between four weeks and six months. Placebo was the control in 24 studies. Overall risk of bias was low for four, high for one and unclear for 22 studies. In adults with asthma, we do not know whether pine bark extract increases change in forced expiratory volume in one second (FEV₁) % predicted/forced vital capacity (FVC) (mean difference (MD) 7.70, 95% confidence interval (CI) 3.19 to 12.21; one study; 44 participants; very low-certainty evidence), increases change in FEV₁ % predicted (MD 7.00, 95% CI 0.10 to 13.90; one study; 44 participants; very low-certainty evidence), improves asthma symptoms (risk ratio (RR) 1.85, 95% CI 1.32 to 2.58; one study; 60 participants; very low-certainty evidence) or increases the number of people able to stop using albuterol inhalers (RR 6.00, 95% CI 1.97 to 18.25; one study; 60 participants; very low-certainty evidence). In children with ADHD, we do not know whether pine bark extract decreases inattention and hyperactivity assessed by parent- and teacher-rating scales (narrative synthesis; one study; 57 participants; very low-certainty evidence) or increases the change in visual-motoric coordination and concentration (MD 3.37, 95% CI 2.41 to 4.33; one study; 57 participants; very low-certainty evidence). In participants with CVD, we do not know whether pine bark extract decreases diastolic blood pressure (MD -3.00 mm Hg, 95% CI -4.51 to -1.49; one study; 61 participants; very low-certainty evidence); increases HDL cholesterol (MD 0.05 mmol/L, 95% CI -0.01 to 0.11; one study; 61 participants; very low-certainty evidence) or decreases LDL cholesterol (MD -0.03 mmol/L, 95% CI -0.05 to 0.00; one study; 61 participants; very low-certainty evidence). In participants with CVI, we do not know whether pine bark extract decreases pain scores (MD -0.59, 95% CI -1.02 to -0.16; one study; 40 participants; very low-certainty evidence), increases the disappearance of pain (RR 25.0, 95% CI 1.58 to 395.48; one study; 40 participants; very low-certainty evidence) or increases physician-judged treatment efficacy (RR 4.75, 95% CI 1.97 to 11.48; 1 study; 40 participants; very low-certainty evidence). In type 2 DM, we do not know whether pine bark extract leads to a greater reduction in fasting blood glucose (MD 1.0 mmol/L, 95% CI 0.91 to 1.09; one study; 48 participants;very low-certainty evidence) or decreases HbA1c (MD -0.90 %, 95% CI -1.78 to -0.02; 1 study; 48 participants; very low-certainty evidence). In a mixed group of participants with type 1 and type 2 DM we do not know whether pine bark extract decreases HbA1c (MD -0.20 %, 95% CI -1.83 to 1.43; one study; 67 participants; very low-certainty evidence). In men with erectile dysfunction, we do not know whether pine bark extract supplements increase International Index of Erectile Function-5 scores (not pooled; two studies; 147 participants; very low-certainty evidence). In women with sexual dysfunction, we do not know whether pine bark extract increases satisfaction as measured by the Female Sexual Function Index (MD 5.10, 95% CI 3.49 to 6.71; one study; 75 participants; very low-certainty evidence) or leads to a greater reduction of pain scores (MD 4.30, 95% CI 2.69 to 5.91; one study; 75 participants; very low-certainty evidence). In adults with osteoarthritis of the knee, we do not know whether pine bark extract decreases composite Western Ontario and McMaster Universities Osteoarthritis Index scores (MD -730.00, 95% CI -1011.95 to -448.05; one study; 37 participants; very low-certainty evidence) or the use of non-steroidal anti-inflammatory medication (MD -18.30, 95% CI -25.14 to -11.46; one study; 35 participants; very low-certainty evidence). We do not know whether pine bark extract increases bone alkaline phosphatase in post-menopausal women with osteopenia (MD 1.16 ug/L, 95% CI -2.37 to 4.69; one study; 40 participants; very low-certainty evidence). In individuals with traumatic brain injury, we do not know whether pine bark extract decreases cognitive failure scores (MD -2.24, 95% CI -11.17 to 6.69; one study; 56 participants; very low-certainty evidence) or post-concussion symptoms (MD -0.76, 95% CI -5.39 to 3.87; one study; 56 participants; very low-certainty evidence). For most comparisons, studies did not report outcomes of hospital admissions or serious adverse events.

AUTHORS' CONCLUSIONS

Small sample sizes, limited numbers of RCTs per condition, variation in outcome measures, and poor reporting of the included RCTs mean no definitive conclusions regarding the efficacy or safety of pine bark extract supplements are possible.

Antioxidant Therapies in Traumatic Brain Injury

Due to a multiplicity of causes provoking traumatic brain injury (TBI), TBI is a highly heterogeneous pathology, characterized by high mortality and disability rates. TBI is an acute neurodegenerative event, potentially and unpredictably evolving into sub-chronic and chronic neurodegenerative events, with transient or permanent neurologic, cognitive, and motor deficits, for which no valid standardized therapies are available. A vast body of literature demonstrates that TBI-induced oxidative/nitrosative stress is involved in the development of both acute and chronic neurodegenerative disorders. Cellular defenses against this phenomenon are largely dependent on low molecular weight antioxidants, most of which are consumed with diet or as nutraceutical supplements. A large number of studies have evaluated the efficacy of antioxidant administration to decrease TBI-associated damage in various animal TBI models and in a limited number of clinical trials. Points of weakness of preclinical studies are represented by the large variability in the TBI model adopted, in the antioxidant tested, in the timing, dosages, and routes of administration used, and in the variety of molecular and/or neurocognitive parameters evaluated. The analysis of the very few clinical studies does not allow strong conclusions to be drawn on the real effectiveness of antioxidant administration to TBI patients. Standardizing TBI models and different experimental conditions, as well as testing the efficacy of administration of a cocktail of antioxidants rather than only one, should be mandatory. According to some promising clinical results, it appears that sports-related concussion is probably the best type of TBI to test the benefits of antioxidant administration.