Search Results (17)

Background: Lower-limb asymmetry is linked to injury risk and may impair performance, yet evidence in basketball is inconsistent. A commonly cited 10% threshold is proposed as critical, but its practical relevance in basketball-specific tasks remains unclear. This study examined the effects of asymmetry on vertical jump and agility performance in basketball players, with particular focus on the 10% threshold. Methods: Male university basketball players (n = 20) completed unilateral jump tests (single-leg countermovement jump, single-hop, triple-hop, 6 m hop) and a bilateral COD (change of direction) test to quantify asymmetry. Basketball-specific performance was evaluated using the Lane Agility Test and bilateral countermovement jump. Asymmetry indices were calculated as absolute percentage differences. Paired tests, Welch’s t-tests (<10% vs. ≥10% asymmetry), and Pearson correlations were applied. Results: Significant inter-limb asymmetries were detected across all unilateral tasks (large effect sizes). Players with ≥10% asymmetry showed reduced bilateral countermovement jump height compared to <10% (p = 0.039, d = 1.00). Triple-hop asymmetry correlated strongly with slower Lane Agility Test times (r = 0.62, p = 0.003), while single-leg jump asymmetry correlated moderately and negatively with bilateral countermovement jump height (r = −0.46, p = 0.043). No significant associations were found for COD asymmetry. Conclusions: In the present study, inter-limb asymmetries exceeding 10% were associated with impaired vertical jump performance. Triple-hop asymmetry appears most relevant for agility, whereas COD asymmetry may not adequately reflect basketball-specific demands. Monitoring and reducing inter-limb asymmetries may support both performance and injury prevention. Full article

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide exerting, among others, strong trophic and protective effects. It plays a role in several physiological functions, including glucose homeostasis. The protective effects of PACAP are mainly mediated via its specific PAC1 receptor by stimulating anti-inflammatory, anti-apoptotic and antioxidant pathways. The aim of the present review is to summarize data on the protective effects of PACAP in the three major complications of diabetes, retinopathy, nephropathy and neuropathy, as well as some other complications. In type 1 and type 2 diabetic retinopathy models and in glucose-exposed cells of the eye, PACAP counteracted the degeneration of retinal layers and inhibited apoptosis and factors leading to abnormal vessel growth. In models of nephropathy, kidney morphology was better retained after PACAP administration, with decreased apoptosis and fibrosis. In diabetic neuropathy, PACAP protected against axonal–myelin lesions and less activation in pain processing centers. This neuropeptide has several other beneficial effects in diabetes-induced complications like altered vascular response, cognitive deficits and atherosclerosis. The promising therapeutic effects of PACAP in several pathological conditions have encouraged researchers to design PACAP-related drugs and to develop ways to enhance tissue delivery. These intentions are expected to result in overcoming the hurdles preventing PACAP from being introduced into therapeutic treatments, including diabetes-related conditions. Full article

The prevalence of hypoxia-caused eye diseases is increasing, but effective, non-invasive treatment options are not available. Abscisic acid (ABA) is a plant hormone with anti-inflammatory and antioxidant effects. ABA is also present in various mammalian tissues and plays an important role in metabolic processes. Therefore, we aimed to investigate the potential protective role of ABA eye drops in ischemic retinopathy. Retinal ischemia was induced by permanent unilateral common carotid artery occlusion (UCCAO) in mice. Half of the animals received ABA eye drops two times a day for two weeks. Optical coherence tomography (OCT) was used to follow the changes in retinal thickness. Moreover, immunohistochemistry and molecular biology methods were used to explore the morphological changes and the underlying mechanisms, respectively. Based on OCT measurements, ischemic retinopathy was successfully developed. The decrease in the thickness of numerous retinal layers could be prevented with ABA eye drops. The ganglion cell number decreased significantly after UCCAO in the central and peripheral regions of the retina. ABA treatment could moderate the damage in both regions. Furthermore, our apoptosis array results suggest that ABA regulates the apoptotic pathways under hypoxic conditions. In conclusion, ABA eye drops may represent a new potential therapeutic option for the treatment of ischemic retinopathy. Full article

(1) Background: Glaucoma is a multifactorial group of diseases characterized by progressive optic neuropathy. Intraocular pressure (IOP) is the only successfully modifiable risk factor for all forms of glaucoma. However, recent research has highlighted the reduction of oxidative stress and neuroinflammation as promising therapeutic targets. In this study, we evaluated the antiglaucomatous effects of a combined herbal extract applied as eye drops in a rat model of glaucoma. (2) Methods: Sprague Dawley rats were divided into four groups: healthy controls, glaucomatous animals treated with preservative-free artificial tears, and healthy and glaucomatous groups receiving combined herbal-based eye drops for 8 weeks. Glaucoma was induced through injection of microbeads into the anterior chamber at week 1 and week 3. Before the first injection and at weeks 4 and 8, rats underwent optical coherence tomography (OCT) and electroretinogram (ERG) recordings. Retinal analyses were conducted to assess retinal ganglion cell (RGC) count, vessel density, and markers of neural pathways, oxidative stress, and inflammation. (3) Results: The combination of herbal extracts showed beneficial effects on IOP elevation, and significantly improved ERG responses. Neuroprotective effects were assessed using OCT, immunohistochemistry, and proteomics. Most parameters in herbal eye drop-treated rats were not statistically different from those in healthy controls. (4) Conclusions: Topical administration of plant-based compounds may serve as an effective supportive therapy for ocular hypertension and retinal neuroprotection. Full article

The continuously growing diabetes population is a significant concern with type 2 diabetic retinal disease (T2DRD), which is a leading cause of permanent blindness. However, the underlying pathophysiological mechanism of T2DRD has not yet been fully understood. Pituitary adenylate cyclase-activating polypeptide (PACAP) was first isolated from the ovine hypothalamus based on its stimulating effect on the adenylate cyclase enzyme in anterior pituitary cells. PACAP38 (PACAP with 38 amino acids) activates anti-apoptotic pathways, inhibits pro-apoptotic signaling, and creates an anti-inflammatory environment in the retina. The aim of the present study was to test the possible retinoprotective effect of the topical administration of PACAP38 in a type 2 diabetic animal model induced by a high-fat diet and the intraperitoneally injected low-dose streptozotocin (STZ). Wistar rats were divided into four groups: the control, control + PACAP38, diabetes, and diabetes + PACAP38 groups randomly. Type 2 diabetes was induced with the combination of STZ (30 mg/kg) and a high-fat diet. All rats were treated topically two times a day for 16 weeks: the control + PACAP38 and diabetes + PACAP38 groups were applied with PACAP38 eye drops (1 µg/drop), while the control and diabetes groups were administered using vehicles (artificial tears). The diabetes model was validated by a fasting oral glucose tolerance test (OGTT) and C-peptide ELISA test. Animals were monitored during the whole experiment for the progression of the disease using electroretinography (ERG) and optical coherence tomography (OCT). Post-mortem immunohistochemistry and a vessel analysis were performed in the retina samples after 16 weeks. An OGTT, a C-peptide ELISA test, and the investigation of blood parameters proved the development of type 2 diabetes. Significant differences could be detected in visual function between the two diabetic groups at week 16 (in the a-wave, b-wave, and OP amplitudes), where the diabetes PACAP38-treated group was similar to the control ones. OCT measurements correlated with ERG data, where the total retinal thickness was preserved in the diabetes + PACAP38 group. PACAP38 also protected the microvascular structure in the retina. Topically administered PACAP38 has potent neuroprotective effects against type 2 diabetic retinal disease; therefore, it could be a promising therapeutic approach for the treatment of T2DRD. Full article

The retina is one of the highest metabolically active tissues with a high oxygen consumption, so insufficient blood supply leads to visual impairment. The incidence of related conditions is increasing; however, no effective treatment without side effects is available. Furthermore, the pathomechanism of these diseases is not fully understood. Our aim was to develop an optimal ischemic retinopathy mouse model to investigate the retinal damage in a time-dependent manner. Retinal ischemia was induced by bilateral common carotid artery occlusion (BCCAO) for 10, 13, 15 or 20 min, or by right permanent unilateral common carotid artery occlusion (UCCAO). Optical coherence tomography was used to follow the changes in retinal thickness 3, 7, 14, 21 and 28 days after surgery. The number of ganglion cells was evaluated in the central and peripheral regions on whole-mount retina preparations. Expression of glial fibrillary acidic protein (GFAP) was analyzed with immunohistochemistry and Western blot. Retinal degeneration and ganglion cell loss was observed in multiple groups. Our results suggest that the 20 min BCCAO is a good model to investigate the consequences of ischemia and reperfusion in the retina in a time-dependent manner, while the UCCAO causes more severe damage in a short time, so it can be used for testing new drugs. Full article

Retinoblastoma represents the most prevalent malignant neoplasm affecting the eyes in childhood. The clear-cut origin of retinoblastoma has not yet been determined; however, based on experiments, it has been suggested that RB1 loss in cone photoreceptors causes retinoblastoma. Pituitary adenylate-cyclase activating polypeptide (PACAP) is a pleiotropic neuropeptide which has been shown to be affected in certain tumorous transformations, such as breast, lung, kidney, pancreatic, colon, and endocrine cancers. This study aimed to investigate potential changes in both PACAP38 and PAC1 receptor (PAC1R) expression in human retinoblastoma and the effect of PACAP38 administration on the survival of a human retinoblastoma cell line (Y-79). We analyzed human enucleation specimens removed because of retinoblastoma for PACAP38 and PAC1R immunostaining and the effect of PACAP38 on the survival of the Y-79 cell line. We described for the first time that human retinoblastoma cells from patients showed only perinuclear, dot-like immunopositivity for both PACAP38 and PAC1R, irrespective of laterality, genetic background, or histopathological features. Nanomolar (100 nM and 500 nM) PACAP38 concentrations had no effect on the viability of Y-79 cells, while micromolar (2 µM and 6 µM) PACAP38 significantly decreased tumor cell viability. These findings, along with general observations from animal studies showing that PACAP38 has strong anti-apoptotic, anti-inflammatory, and antioxidant effects on ocular tissues, together suggest that PACAP38 and its analogs are promising candidates in retinoblastoma therapy. Full article

Despite the high probability of glaucoma-related blindness, its cause is not fully understood and there is no efficient therapeutic strategy for neuroprotection. Vascular factors have been suggested to play an important role in glaucoma development and progression. Previously, we have proven the neuroprotective effects of pituitary adenylate-cyclase-activating polypeptide (PACAP) eye drops in an inducible, microbeads model in rats that is able to reproduce many clinically relevant features of human glaucoma. In the present study, we examined the potential protective effects of PACAP1-38 on the retinal vasculature and the molecular changes in hypoxia. Ocular hypertension was induced by injection of microbeads into the anterior chamber, while control rats received PBS. PACAP dissolved in vehicle (1 µg/drop) or vehicle treatment was started one day after the injections for four weeks three times a day. Retinal degeneration was assessed with optical coherence tomography (OCT), and vascular and molecular changes were assessed by immunofluorescence labeling. HIF1-α and VEGF-A protein levels were measured by Western blot. OCT images proved severe retinal degeneration in the glaucomatous group, while PACAP1-38 eye drops had a retinoprotective effect. Vascular parameters were deteriorated and molecular analysis suggested hypoxic conditions in glaucoma. PACAP treatment exerted a positive effect against these alterations. In summary, PACAP could prevent the severe damage to the retina and its vasculature induced by ocular hypertension in a microbeads model. Full article

Studies have proven the effectiveness of different weight-bearing exercise interventions for diabetic patients with neuropathy; however, several adverse effects were reported using solid surfaces. Thus, in the present study, we investigated the effects of a novel sand exercise training intervention on biomechanical and functional parameters in seven diabetic patients (age = 62.7 ± 9.7 years) with neuropathy. Patients underwent a 12-week sand exercise training program, using strengthening, stretching, balance, and gait exercises. They were tested for ankle plantar- and dorsiflexion peak torque, active range of motion (ROM), timed up and go (TUG), and bilateral static balance. EMG activity of tibialis anterior (TA), gastrocnemius medialis (GM), and lateralis (GL) muscles were measured during unilateral isometric contraction in plantar- and dorsiflexion. In the intervention period, plantarflexion peak torque improved significantly (p = 0.033), while dorsiflexion torque remained unchanged. Plantar- and dorsiflexion ROM increased (p = 0.032) and (p = 0.021), respectively. EMG activity of GM (p = 0.005) and GL (p = 0.002) measured during dorsiflexion and postural sway in the balance test, as well as time to complete the TUG test, decreased significantly (p = 0.021) and (p = 0.002), respectively. No adverse effect was reported during the intervention period. We concluded that sand exercise training can be a safe and effective method to improve plantarflexion strength, ankle flexibility, and balance, which is reflected in better gait function in patients with diabetic peripheral neuropathy (DPN). Full article

(1) The unilateral countermovement jump is commonly used to examine frontal plane kinetics during unilateral loading and to identify athletes with an increased risk of lower limb injuries. In the present study, we examined the biomechanical mechanisms of knee and pelvis stabilization during unilateral vertical jumps. (2) Healthy males performed jumps on a force plate with the dominant leg. Activity of the dominant-side gluteus medius and the contralateral-side quadratus lumborum and erector spinae muscles was recorded with surface EMG. The EMG data were normalized to the EMG activity recorded during maximal voluntary isometric hip abduction and lateral trunk flexion contractions. During jumps, the propulsive impulse was measured, and the pelvis and thigh segmental orientation angles in the frontal plane were recorded and synchronized with the EMG data. (3) The magnitude of knee valgus during the jump did not correlate with hip abduction force, but negatively correlated with gluteus medius activity. This correlation became stronger when gluteus medius activity was normalized to hip abduction force. Propulsive impulse did not correlate with any neuromechanical measurement. (4) We conclude that hip abduction force itself does not regulate the magnitude of knee valgus during unilateral jumps; rather, the gluteus medius should be highly activated to increase frontal-plane knee joint stability. Full article

Songorine (SON) is a diterpenoid alkaloid from Aconitum plants. Preparations of Aconitum roots have been employed in traditional oriental herbal medicine, however, their mechanisms of action are still unclear. Since GABA-receptors are possible brain targets of SON, we investigated which subtypes of GABA-receptors contribute to the effects of SON, and how SON affects anxiety-like trait behavior and psychomotor cognitive performance of rats. First, we investigated the effects of microiontophoretically applied SON alone and combined with GABA-receptor agents picrotoxin and saclofen on neuronal firing activity in various brain areas. Next, putative anxiolytic effects of SON (1.0–3.0 mg/kg) were tested against the GABA-receptor positive allosteric modulator reference compound diazepam (1.0–5.0 mg/kg) in the elevated zero maze (EOM). Furthermore, basic cognitive effects were assessed in a rodent version of the psychomotor vigilance task (PVT). Local application of SON predominantly inhibited the firing activity of neurons. This inhibitory effect of SON was successfully blocked by GABA(A)-receptor antagonist picrotoxin but not by GABA(B)-receptor antagonist saclofen. Similar to GABA(A)-receptor positive allosteric modulator diazepam, SON increased the time spent by animals in the open quadrants of the EOM without any signs of adverse psychomotor and cognitive effects observed in the PVT. We showed that, under in vivo conditions, SON acts as a potent GABA(A)-receptor agonist and effectively decreases anxiety without observable side effects. The present findings facilitate the deeper understanding of the mechanism of action and the widespread pharmacological use of diterpene alkaloids in various CNS indications. Full article

Aim The aim of the study was to investigate acute and chronic effects of a two-week eccentric concentric, dynamometric training concerning the time-course changes of blood antioxidant parameters (total antioxidant capacity, catalase enzyme activity, thiol concentration), and to compare the adaptability of young and older muscle to this type of training. Methods Seventeen moderately trained young and older men participated in this research. Subjects performed six eccentric concentric exercise bouts during the training period and maximal voluntary isometric contraction torque, plasma CK and intensity of muscle soreness were determined before and 24 h after the first exercise. During five testing sessions (baseline, 24 h, 48 h, week 1, week 2) the level of blood antioxidants were measured. Results No significant changes were registered in total antioxidant capacity and catalase enzyme activity for any time points; furthermore, no difference was found between groups during the training period. However, total thiol concentrations measured two weeks after the first exercise bout significantly differed between the young and elderly groups. Plasma CK and the subjective intensity of soreness elevated significantly 24 h following the first training, while maximal voluntary isometric contraction torque decreased at the same time. Conclusions Our results do not support previous findings that chronic, short-term eccentric concentric training programs enhance the antioxidant defense of well-trained older and young men. This type and setting of exercise did not cause a different time course of changes in the markers of exercise-induced muscle damage (EIMD) in the studied population. Subjects may already have adapted to maintain constant levels of antioxidants and isometric torque due to their active lifestyle. Full article

Glaucoma is associated with increased intraocular pressure (IOP), causing the apoptosis of retinal ganglion cells (RGCs) and the loss of their axons leading to blindness. Pituitary adenylate cyclase activating polypeptide (PACAP) is neuroprotective in several neural injuries, including retinopathies. The aim of this study was to investigate the effects of PACAP1-38 eye drops in a model of glaucoma. IOP was elevated bilaterally by injections of microbeads to block the aqueous humor outflow. The control groups received the same volume of saline. Animals were treated with PACAP1-38 (1 µg/drop, 3 × 1 drop/day) or vehicle for 4 weeks starting one day after the injections. Retinal morphology by histology and optical coherence tomography, function by electroretinography, and IOP changes were analyzed. Animals were sacrificed 8 weeks after the injections. Microbeads injections induced a significant increase in the IOP, while PACAP1-38 treatment lowered it to normal levels (~10 mmHg). Significant retinal degeneration and functional impairment were observed in the microbead-injected group without PACAP1-38 treatment. In the microbeads + PACAP1-38 group, the retinal morphology and functionality were close to the normal values. In summary, our results show that PACAP1-38, given in form of eye drops, is neuroprotective in glaucoma, providing the basis for potential future therapeutic administration. Full article

(1) In the present investigation, we tested the hypothesis that unilateral countermovement jump performance is associated with knee joint stabilization ability during unilateral landing on unstable surface. (2) Twenty-five male sport students were tested for dynamometric knee extension and flexion, and hip abduction isometric strength. Myolectric activity of vastus lateralis and medialis, gluteus medius, and biceps femoris muscles were measured during unilateral countermovement vertical jump performed on a force plate, and during unilateral landing on unstable surface. (3) Vertical jump impulse negatively correlated with biceps femoris activation at landing. Participants with greater hip abduction force performed greater vertical jump impulse, and activated the biceps femoris less when landing on unstable surface. Furthermore, participants with smaller knee flexion/extension torque ratio increased biceps femoris/vastus medialis activation ratio at landing. (4) We conclude that hip abduction strength is an important contributor to unilateral vertical jump performance. Because biceps femoris is considered the synergist of the anterior cruciate ligament, we also propose that hip abductors are primary frontal plane protectors of the knee joint by reducing knee valgus and stress, allowing for smaller biceps femoris co-activation (secondary protection) at landing on unstable surface. Full article

The high prevalence of obesity in childhood and adolescence has major public health consequences, since it is associated with various chronic diseases in the short- and long-term. The goal of our study was to examine the possible association between obesity and overweight and cardiorespiratory and muscle performance during a 4-year follow up period in adolescents. The body mass index (BMI) and physical performance of adolescents (360 girls and 348 boys) between 14–18 years of age was measured twice a year, and the possible correlation between overweight and obesity and cardiorespiratory and muscle performances were investigated. Our results revealed that cardiorespiratory performance increased significantly in boys during the 4 years (p < 0.001), but the aerobic performance of girls only showed seasonal fluctuation. Muscle performance significantly increased both in boys and girls (p < 0.001). Inverse association between obesity and cardiorespiratory and muscle performance was proved. Overweight was also inversely correlated with cardiorespiratory performance, but it demonstrated no correlation with muscle strength. Avoiding increased BMI and decreased physical fitness is essential for adolescents’ health to prevent short- and long-term adverse effects. Full article