Human conditions of insulin-like growth factor-I (IGF-I) deficiency

Sex-specific single cell-level transcriptomic signatures of Rett syndrome disease progression

Dominant X-linked diseases are uncommon due to female X chromosome inactivation (XCI). While random XCI usually protects females against X-linked mutations, Rett syndrome (RTT) is a female neurodevelopmental disorder caused by heterozygous MECP2 mutation. After 6-18 months of typical neurodevelopment, RTT girls undergo a poorly understood regression. We performed longitudinal snRNA-seq on cerebral cortex in a construct-relevant Mecp2e1 mutant mouse model of RTT, revealing transcriptional effects of cell type, mosaicism, and sex on progressive disease phenotypes. Across cell types, we observed sex differences in the number of differentially expressed genes (DEGs) with 6x more DEGs in mutant females than males. Unlike males, female DEGs emerged prior to symptoms, were enriched for homeostatic gene pathways in distinct cell types over time and correlated with disease phenotypes and human RTT cortical cell transcriptomes. Non-cell-autonomous effects were prominent and dynamic across disease progression of Mecp2e1 mutant females, indicating that wild-type-expressing cells normalize transcriptional homeostasis. These results advance our understanding of RTT progression and treatment.

Impact of different hormones on the regulation of nitric oxide in diabetes

Polymetabolic syndrome achieved pandemic proportions and dramatically influenced public health systems functioning worldwide. Chronic vascular complications are the major contributors to increased morbidity, disability, and mortality rates in diabetes patients. Nitric oxide (NO) is among the most important vascular bed function regulators. However, NO homeostasis is significantly deranged in pathological conditions. Additionally, different hormones directly or indirectly affect NO production and activity and subsequently act on vascular physiology. In this paper, we summarize the recent literature data related to the effects of insulin, estradiol, insulin-like growth factor-1, ghrelin, angiotensin II and irisin on the NO regulation in physiological and diabetes circumstances.

New Insights into IGF-1 Signaling in the Heart

Insulin-like growth factor-1 (IGF-1) signaling has multiple physiological roles in cellular growth, metabolism, and aging. Myocardial hypertrophy, cell death, senescence, fibrosis, and electrical remodeling are hallmarks of various heart diseases and contribute to the progression of heart failure. This review highlights the critical role of IGF-1 and its cognate receptor in cardiac hypertrophy, aging, and remodeling.

Vascular smooth muscle cell-specific Igf1r deficiency exacerbates the development of hypertension-induced cerebral microhemorrhages and gait defects

Cerebrovascular fragility and cerebral microhemorrhages (CMH) contribute to age-related cognitive impairment, mobility defects, and vascular cognitive impairment and dementia, impairing healthspan and reducing quality of life in the elderly. Insulin-like growth factor 1 (IGF-1) is a key vasoprotective growth factor that is reduced during aging. Circulating IGF-1 deficiency leads to the development of CMH and other signs of cerebrovascular dysfunction. Here our goal was to understand the contribution of IGF-1 signaling on vascular smooth muscle cells (VSMCs) to the development of CMH and associated gait defects. We used an inducible VSMC-specific promoter and an IGF-1 receptor (Igf1r) floxed mouse line (Myh11-CreERT2 Igf1rf/f) to knockdown Igf1r. Angiotensin II in combination with L-NAME-induced hypertension was used to elicit CMH. We observed that VSMC-specific Igf1r knockdown mice had accelerated development of CMH, and subsequent associated gait irregularities. These phenotypes were accompanied by upregulation of a cluster of pro-inflammatory genes associated with VSMC maladaptation. Collectively our findings support an essential role for VSMCs as a target for the vasoprotective effects of IGF-1, and suggest that VSMC dysfunction in aging may contribute to the development of CMH.

Insulin-like growth factor family and prostate cancer: new insights and emerging opportunities

Prostate cancer is the second most commonly diagnosed cancer in men. The mammalian insulin-like growth factor (IGF) family is made up of three ligands (IGF-I, IGF-II, and insulin), three receptors (IGF-I receptor (IGF-1R), insulin receptor (IR), and IGF-II receptor (IGF-2R)), and six IGF-binding proteins (IGFBPs). IGF-I and IGF-II were identified as potent mitogens and were previously associated with an increased risk of cancer development including prostate cancer. Several reports showed controversy about the expression of the IGF family and their connection to prostate cancer risk due to the high degree of heterogeneity among prostate tumors, sampling bias, and evaluation techniques. Despite that, it is clear that several IGF family members play a role in prostate cancer development, metastasis, and androgen-independent progression. In this review, we aim to expand our understanding of prostate tumorigenesis and regulation through the IGF system. Further understanding of the role of IGF signaling in PCa shows promise and needs to be considered in the context of a comprehensive treatment strategy.

Sex-specific single cell-level transcriptomic signatures of Rett syndrome disease progression

Dominant X-linked diseases are uncommon due to female X chromosome inactivation (XCI). While random XCI usually protects females against X-linked mutations, Rett syndrome (RTT) is a female neurodevelopmental disorder caused by heterozygous MECP2 mutation. After 6-18 months of typical neurodevelopment, RTT girls undergo poorly understood regression. We performed longitudinal snRNA-seq on cerebral cortex in a construct-relevant Mecp2e1 mutant mouse model of RTT, revealing transcriptional effects of cell type, mosaicism, and sex on progressive disease phenotypes. Across cell types, we observed sex differences in the number of differentially expressed genes (DEGs) with 6x more DEGs in mutant females than males. Unlike males, female DEGs emerged prior to symptoms, were enriched for homeostatic gene pathways in distinct cell types over time, and correlated with disease phenotypes and human RTT cortical cell transcriptomes. Non-cell-autonomous effects were prominent and dynamic across disease progression of Mecp2e1 mutant females, indicating wild-type-expressing cells normalizing transcriptional homeostasis. These results improve understanding of RTT progression and treatment.

Hydrogel-based cardiac repair and regeneration function in the treatment of myocardial infarction

A life-threatening illness that poses a serious threat to human health is myocardial infarction. It may result in a significant number of myocardial cells dying, dilated left ventricles, dysfunctional heart function, and ultimately cardiac failure. Based on the development of emerging biomaterials and the lack of clinical treatment methods and cardiac donors for myocardial infarction, hydrogels with good compatibility have been gradually applied to the treatment of myocardial infarction. Specifically, based on the three processes of pathophysiology of myocardial infarction, we summarized various types of hydrogels designed for myocardial tissue engineering in recent years, including natural hydrogels, intelligent hydrogels, growth factors, stem cells, and microRNA-loaded hydrogels. In addition, we also describe the heart patch and preparation techniques that promote the repair of MI heart function. Although most of these hydrogels are still in the preclinical research stage and lack of clinical trials, they have great potential for further application in the future. It is expected that this review will improve our knowledge of and offer fresh approaches to treating myocardial infarction.

The Effect of a Rotating Magnetic Field on the Regenerative Potential of Platelets

Platelets are actively involved in tissue injury site regeneration by producing a wide spectrum of platelet-derived growth factors such as PDGF (platelet-derived growth factor), IGF-1 (insulin-like growth factor), TGF-β1 (transforming growth factor β), FGF (fibroblast growth factor), etc. A rotating magnetic field (RMF) can regulate biological functions, including reduction or induction regarding inflammatory processes, cell differentiation, and gene expression, to determine the effect of an RMF on the regenerative potential of platelets. The study group consisted of 30 healthy female and male volunteers (n = 15), from which plasma was collected. A portion of the plasma was extracted and treated as an internal control group. Subsequent doses of plasma were exposed to RMF at different frequencies (25 and 50 Hz) for 1 and 3 h. Then, the concentrations of growth factors (IGF-1, PDGF-BB, TGF-β1, and FGF-1) were determined in the obtained material by the ELISA method. There were statistically significant differences in the PDGF-BB, TGF-β1, IGF-1, and FGF-1 concentrations between the analyzed groups. The highest concentration of PDGF-BB was observed in the samples placed in RMF for 1 h at 25 Hz. For TGF-β1, the highest concentrations were obtained in the samples exposed to RMF for 3 h at 25 Hz and 1 h at 50 Hz. The highest concentrations of IGF-1 and FGF-1 were shown in plasma placed in RMF for 3 h at 25 Hz. An RMF may increase the regenerative potential of platelets. It was noted that female platelets may respond more strongly to RMF than male platelets.

Hydrogels for Cardio and Vascular Tissue Repair and Regeneration

Cardiovascular disease (CVD), the leading cause of death globally, affects the heart and arteries with a variety of clinical manifestations, the most dramatic of which are myocardial infarction (MI), abdominal aortic aneurysm (AAA), and intracranial aneurysm (IA) rupture. In MI, necrosis of the myocardium, scar formation, and loss of cardiomyocytes result from insufficient blood supply due to coronary artery occlusion. Beyond stenosis, the arteries that are structurally and functionally connected to the cardiac tissue can undergo pathological dilation, i.e., aneurysmal dilation, with high risk of rupture. Aneurysms of the intracranial arteries (IAs) are more commonly seen in young adults, whereas those of the abdominal aorta (AAA) are predominantly seen in the elderly. IAs, unpredictably, can undergo rupture and cause life-threatening hemorrhage, while AAAs can result in rupture, internal bleeding and high mortality rate. In this clinical context, hydrogels, three-dimensional networks of water-seizing polymers, have emerged as promising biomaterials for cardiovascular tissue repair or protection due to their biocompatibility, tunable properties, and ability to encapsulate and release bioactive molecules. This review provides an overview of the current state of research on the use of hydrogels as an innovative platform to promote cardiovascular-specific tissue repair in MI and functional recovery or protection in aneurysmal dilation.

Tirzepatide prevents neurodegeneration through multiple molecular pathways

BACKGROUND

Several evidence demonstrated that glucagon-like peptide 1 receptor agonists (GLP1-RAs) reduce the risk of dementia in type 2 diabetes patients by improving memory, learning, and overcoming cognitive impairment. In this study, we elucidated the molecular processes underlying the protective effect of Tirzepatide (TIR), a dual glucose-dependent insulinotropic polypeptide receptor agonist (GIP-RA)/ GLP-1RA, against learning and memory disorders.

METHODS

We investigated the effects of TIR on markers of neuronal growth (CREB and BDNF), apoptosis (BAX/Bcl2 ratio) differentiation (pAkt, MAP2, GAP43, and AGBL4), and insulin resistance (GLUT1, GLUT4, GLUT3 and SORBS1) in a neuroblastoma cell line (SHSY5Y) exposed to normal and high glucose concentration. The potential role on DNA methylation of genes involved in neuroprotection and epigenetic modulators of neuronal growth (miRNA 34a), apoptosis (miRNA 212), and differentiation (miRNA 29c) was also investigated. The cell proliferation was detected by measuring Ki-67 through flow cytometry. The data were analysed by SPSS IBM Version 23 or GraphPad Prism 7.0 software and expressed as the means ± SEM. Differences between the mean values were considered significant at a p-value of < 0.05. GraphPad Prism software was used for drawing figures.

RESULTS

For the first time, it was highlighted: (a) the role of TIR in the activation of the pAkt/CREB/BDNF pathway and the downstream signaling cascade; (b) TIR efficacy in neuroprotection; (c) TIR counteracting of hyperglycemia and insulin resistance-related effects at the neuronal level.

CONCLUSIONS

We demonstrated that TIR can ameliorate high glucose-induced neurodegeneration and overcome neuronal insulin resistance. Thus, this study provides new insight into the potential role of TIR in improving diabetes-related neuropathy.

Insulin Signaling Through the Insulin Receptor Increases Linear Growth Through Effects on Bone and the GH-IGF-1 Axis

CONTEXT

Childhood overnutrition is associated with increased growth and bone mineral density (BMD) vs the opposite for undernutrition. The role of insulin receptor (InsR) signaling in these phenotypes is unclear. Rare disease patients with hyperinsulinemia and impaired InsR function (homozygous [-/-] or heterozygous [+/-] INSR pathogenic variants, type B insulin resistance [TBIR]) model increased InsR signaling, while patients with intact InsR function (congenital generalized lipodystrophy, CGL) model decreased InsR signaling.

OBJECTIVE

This work aimed to understand mechanisms whereby InsR signaling influences growth.

METHODS

A cross-sectional comparison was conducted of CGL (N = 23), INSR-/- (N = 13), INSR+/- (N = 17), and TBIR (N = 8) at the National Institutes of Health. Main outcome measures included SD scores (SDS) for height, body mass index, insulin-like growth factor (IGF)-1, and BMD, and IGF binding proteins (IGFBP)-1 and -3.

RESULTS

INSR-/- vs CGL had higher insulin (median 266 [222-457] vs 33 [15-55] mcU/mL), higher IGFBP-1 (72 350 [55 571-103 107] vs 6453 [1634-26 674] pg/mL), lower BMI SDS (-0.7 ± 1.1 vs 0.5 ± 0.9), lower height SDS (-1.9[-4.3 to -1.3] vs 1.1 [0.5-2.5]), lower BMD SDS (-1.9 ± 1.4 vs 1.9 ± 0.7), and lower IGFBP-3 (0.37 [0.19-1.05] vs 2.00 [1.45-2.67] μg/mL) (P < .05 for all). INSR +/- were variable. Remission of TBIR lowered insulin and IGFBP-1, and increased IGF-1 and IGFBP-3 (P < .05).

CONCLUSION

Patients with hyperinsulinemia and impaired InsR function exhibit impaired growth and lower BMD, whereas elevated InsR signaling (CGL) causes accelerated growth and higher BMD. These patients demonstrate that insulin action through the InsR stimulates direct anabolic effects in bone and indirect actions through the growth hormone (GH)-IGF-1 axis. TBIR patients exhibit abnormalities in the GH axis that resolve when InsR signaling is restored, supporting a causal relationship between InsR and GH axis signaling.

Impose of KNDy/GnRH neural circuit in PCOS, ageing, cancer and Alzheimer's disease: StAR actions in prevention of neuroendocrine dysfunction

The Kisspeptin1 (KISS1)/neurokinin B (NKB)/Dynorphin (Dyn) [KNDy] neurons in the hypothalamus regulate the reproduction stage in human beings and rodents. KNDy neurons co-expressed all KISS1, NKB, and Dyn peptides, and hence commonly regarded as KISS1 neurons. KNDy neurons contribute to the "GnRH pulse generator" and are implicated in the regulation of pulsatile GnRH release. The estradiol (E2)-estrogen receptor (ER) interactions over GnRH neurons in the hypothalamus cause nitric oxide (NO) discharge, in addition to presynaptic GABA and glutamate discharge from respective neurons. The released GABA and glutamate facilitate the activity of GnRH neurons via GABAA-R and AMPA/kainate-R. The KISS1 stimulates MAPK/ERK1/2 signaling and cause the release of Ca2+ from intracellular store, which contribute to neuroendocrine function, increase apoptosis and decrease cell proliferation and metastasis. The ageing in women deteriorates KISS1/KISS1R interaction in the hypothalamus which causes lower levels of GnRH. Because examining the human brain is so challenging, decades of clinical research have failed to find the causes of KNDy/GnRH dysfunction. The KISS1/KISS1R interactions in the brain have a neuroprotective effect against Alzheimer's disease (AD). These findings modulate the pathophysiological role of the KNDy/GnRH neural network in polycystic ovarian syndrome (PCOS) associated with ageing and, its protective role in cancer and AD. This review concludes with protecting effect of the steroid-derived acute regulatory enzyme (StAR) against neurotoxicity in the hippocampus, and hypothalamus, and these measures are fundamental for delaying ageing with PCOS. StAR could serve as novel diagnostic marker and therapeutic target for the most prevalent hormone-sensitive breast cancers (BCs).

Challenges in the care of individuals with severe primary insulin-like growth factor-I deficiency (SPIGFD): an international, multi-stakeholder perspective

BACKGROUND

Severe primary insulin-like growth factor-I (IGF-I) deficiency (SPIGFD) is a rare growth disorder characterized by short stature (standard deviation score [SDS] ≤ 3.0), low circulating concentrations of IGF-I (SDS ≤ 3.0), and normal or elevated concentrations of growth hormone (GH). Laron syndrome is the best characterized form of SPIGFD, caused by a defect in the GH receptor (GHR) gene. However, awareness of SPIGFD remains low, and individuals living with SPIGFD continue to face challenges associated with diagnosis, treatment and care.

OBJECTIVE

To gather perspectives on the key challenges for individuals and families living with SPIGFD through a multi-stakeholder approach. By highlighting critical gaps in the awareness, diagnosis, and management of SPIGFD, this report aims to provide recommendations to improve care for people affected by SPIGFD globally.

METHODS

An international group of clinical experts, researchers, and patient and caregiver representatives from the SPIGFD community participated in a virtual, half-day meeting to discuss key unmet needs and opportunities to improve the care of people living with SPIGFD.

RESULTS

As a rare disorder, limited awareness and understanding of SPIGFD amongst healthcare professionals (HCPs) poses significant challenges in the diagnosis and treatment of those affected. Patients often face difficulties associated with receiving a formal diagnosis, delayed treatment initiation and limited access to appropriate therapy. This has a considerable impact on the physical health and quality of life for patients, highlighting a need for more education and clearer guidance for HCPs. Support from patient advocacy groups is valuable in helping patients and their families to find appropriate care. However, there remains a need to better understand the burden that SPIGFD has on individuals beyond height, including the impact on physical, emotional, and social wellbeing.

CONCLUSIONS

To address the challenges faced by individuals and families affected by SPIGFD, greater awareness of SPIGFD is needed within the healthcare community, and a consensus on best practice in the care of individuals affected by this condition. Continued efforts are also needed at a global level to challenge existing perceptions around SPIGFD, and identify solutions that promote equitable access to appropriate care. Medical writing support was industry-sponsored.

Living in a hypoxic world: A review of the impacts of hypoxia on aquaculture

Hypoxia is a harmful result of anthropogenic climate change. With the expansion of global low-oxygen zones (LOZs), many organisms have faced unprecedented challenges affecting their survival and reproduction. Extensive research has indicated that oxygen limitation has drastic effects on aquatic animals, including on their development, morphology, behavior, reproduction, and physiological metabolism. In this review, the global distribution and formation of LOZs were analyzed, and the impacts of hypoxia on aquatic animals and the molecular responses of aquatic animals to hypoxia were then summarized. The commonalities and specificities of the response to hypoxia in aquatic animals in different LOZs were discussed lastly. In general, this review will deepen the knowledge of the impacts of hypoxia on aquaculture and provide more information and research directions for the development of fishery resource protection strategies.

Modulation of neurotrophic factors in the treatment of dementia, stroke and TBI: Effects of Cerebrolysin

Neurotrophic factors (NTFs) are involved in the pathophysiology of neurological disorders such as dementia, stroke and traumatic brain injury (TBI), and constitute molecular targets of high interest for the therapy of these pathologies. In this review we provide an overview of current knowledge of the definition, discovery and mode of action of five NTFs, nerve growth factor, insulin-like growth factor 1, brain derived NTF, vascular endothelial growth factor and tumor necrosis factor alpha; as well as on their contribution to brain pathology and potential therapeutic use in dementia, stroke and TBI. Within the concept of NTFs in the treatment of these pathologies, we also review the neuropeptide preparation Cerebrolysin, which has been shown to resemble the activities of NTFs and to modulate the expression level of endogenous NTFs. Cerebrolysin has demonstrated beneficial treatment capabilities in vitro and in clinical studies, which are discussed within the context of the biochemistry of NTFs. The review focuses on the interactions of different NTFs, rather than addressing a single NTF, by outlining their signaling network and by reviewing their effect on clinical outcome in prevalent brain pathologies. The effects of the interactions of these NTFs and Cerebrolysin on neuroplasticity, neurogenesis, angiogenesis and inflammation, and their relevance for the treatment of dementia, stroke and TBI are summarized.

Intrathymic somatotropic circuitry: consequences upon thymus involution

Growth hormone (GH) is a classic pituitary-derived hormone crucial to body growth and metabolism. In the pituitary gland, GH production is stimulated by GH-releasing hormone and inhibited by somatostatin. GH secretion can also be induced by other peptides, such as ghrelin, which interacts with receptors present in somatotropic cells. It is well established that GH acts directly on target cells or indirectly by stimulating the production of insulin-like growth factors (IGFs), particularly IGF-1. Notably, such somatotropic circuitry is also involved in the development and function of immune cells and organs, including the thymus. Interestingly, GH, IGF-1, ghrelin, and somatostatin are expressed in the thymus in the lymphoid and microenvironmental compartments, where they stimulate the secretion of soluble factors and extracellular matrix molecules involved in the general process of intrathymic T-cell development. Clinical trials in which GH was used to treat immunocompromised patients successfully recovered thymic function. Additionally, there is evidence that the reduction in the function of the somatotropic axis is associated with age-related thymus atrophy. Treatment with GH, IGF-1 or ghrelin can restore thymopoiesis of old animals, thus in keeping with a clinical study showing that treatment with GH, associated with metformin and dehydroepiandrosterone, could induce thymus regeneration in healthy aged individuals. In conclusion, the molecules of the somatotrophic axis can be envisioned as potential therapeutic targets for thymus regeneration in age-related or pathological thymus involution.

Recombinant expression of IGF-1 and LR3 IGF-1 fused with xylanase in Pichia pastoris

Insulin-like growth factor-1 (IGF-1) is a pleiotropic protein hormone and has become an attractive therapeutic target because of its multiple roles in various physiological processes, including growth, development, and metabolism. However, its production is hindered by low heterogenous protein expression levels in various expression systems and hard to meet the needs of clinical and scientific research. Here, we report that human IGF-1 and its analog Long R3 IGF-1 (LR3 IGF-1) are recombinant expressed and produced in the Pichia pastoris (P. pastoris) expression system through being fused with highly expressed xylanase XynCDBFV. Furthermore, purified IGF-1 and LR3 IGF-1 display excellent bioactivity of cell proliferation compared to the standard IGF-1. Moreover, higher heterologous expression levels of the fusion proteins XynCDBFV-IGF-1 and XynCDBFV-LR3 IGF-1 are achieved by fermentation in a 15-L bioreactor, reaching up to about 0.5 g/L XynCDBFV-IGF-1 and 1 g/L XynCDBFV-TEV-LR3 IGF-1. Taken together, high recombinant expression of bioactive IGF-1 and LR3 IGF-1 is acquired with the assistance of xylanase as a fusion partner in P. pastoris, which could be used for both clinical and scientific applications. KEY POINTS: • Human IGF-1 and LR3 IGF-1 are produced in the P. pastoris expression system. • Purified IGF-1 and LR3 IGF-1 show bioactivity comparable to the standard IGF-1. • High heterologous expression of IGF-1 and LR3 IGF-1 is achieved by fermentation in a bioreactor.

Evaluation of circulating insulin-like growth factor-1, heart-type fatty acid-binding protein, and endotrophin levels as prognostic markers of COVID-19 infection severity

BACKGROUND

Coronavirus Disease 2019 (COVID-19) is a worldwide pandemic challenge spreading enormously within a few months. COVID-19 is characterized by the over-activation of the immune system causing cytokine storm. Insulin-like growth factor-1 (IGF-1) pathway can regulate the immune response via interaction with various implicated cytokines. Heart-type fatty acid-binding protein (H-FABP) has been shown to promote inflammation. Given the fact that coronavirus infections induce cytokines secretion leading to inflammatory lung injury, it has been suggested that H-FABP levels are affected by COVID-19 severity. Moreover, endotrophin (ETP), the cleavage product of collagen VI, may be an indicator of an overactive repair process and fibrosis, considering that viral infection may predispose or exacerbate existing respiratory conditions, including pulmonary fibrosis. This study aims to assess the prognostic capacity of circulating IGF-1, HFABP, and ETP, levels for COVID-19 severity progression in Egyptian patients.

METHODS

The study cohort included 107 viral RNA-positive patients and an equivalent number of control individuals with no clinical signs of infection. Clinical assessments included profiling of CBC; serum iron; liver and kidney functions; inflammatory markers. Circulating levels of IGF-1; H-FABP, and ETP were estimated using the corresponding ELISA kits.

RESULTS

No statistical difference in the body mass index was detected between the healthy and control groups, while the mean age of infected patients was significantly higher (P = 0.0162) than the control. Patients generally showed elevated levels of inflammatory markers including CRP and ESR concomitant with elevated serum ferritin; D dimer and procalcitonin levels, besides the COVID-19 characteristic lymphopenia and hypoxemia were also frequent. Logistic regression analysis revealed that oxygen saturation; serum IGF-1, and H-FABP can significantly predict the infection progression (P < 0.001 each). Both serum IGF-1 and H-FABP as well as O₂ saturation showed remarkable prognostic potentials in terms of large AUC values, high sensitivity/specificity values, and wide confidence interval. The calculated threshold for severity prognosis was 25.5 ng/mL; 19.5 ng/mL, 94.5, % and for IGF-1, H-FABP, and O₂ saturation; respectively. The calculated thresholds of serum IGF-1; H-FABP, and O₂ saturation showed positive and negative value ranges of 79-91% and 72-97%; respectively, with 66-95%, 83-94% sensitivity, and specificity; respectively.

CONCLUSION

The calculated cut-off values of serum IGF-1 and H-FABP represent a promising non-invasive prognostic tool that would facilitate the risk stratification in COVID-19 patients, and control the morbidity/mortality associated with progressive infection.

Capillary blood as a complementary matrix for doping control purposes. Application to the definition of the individual longitudinal profile of IGF-1

We present a novel procedure to monitor the fluctuations of the levels of IGF-1 in capillary blood in the framework of doping control analysis. Being an endogenous hormone, direct methods are not applicable, so the most effective way to detect the intake of the exogenous hormone would be based on the longitudinal monitoring of the athlete. We have therefore followed the individual variability, in four subjects (two males and two females), of the levels of IGF-1 in capillary blood samples collected three times per day for five days, then once a week for at least two months. Analyses were performed by liquid chromatography coupled to tandem mass spectrometry following a bottom-up approach. The whole protocol, from the sample collection to the instrumental analysis, was validated according to the World Anti-Doping Agency's guidelines and ISO17025. The analytical protocol showed to be fit for purpose in terms of sensitivity (LOD 25 ng/mL and LOI 35 ng/mL), selectivity (no interferences were detected at the retention time of IGF-1 and the internal standard), and repeatability (CV<10%). The linearity was confirmed in the range of 50-1000 ng/mL (correlation coefficient R² >0.995, with a % relative bias of the experimental concentration of the different calibrators used for the estimation of the linearity lower than 20% for the lowest level and than 15% for the other levels). Stability studies were also performed, also to establish the optimal conditions for transport and storage: samples were stable at 4 °C for up to 72 h and at -20 °C and -80 °C for up to three months. Our preliminary results indicate that, in all subjects, the levels of IGF-1 did not present significant circadian fluctuations and remained stable during the entire period of the study (2-3 months, depending on the subject). The stability over time of IGF-1 levels in capillary blood indicates the possibility of detecting the intake of the non-endogenous hormone based on a longitudinal approach, as it is modeled in the framework of the endocrinological module of the athlete biological passport.

The impact of different calibration matrices on the determination of insulin-like growth factor 1 by high-resolution-LC-MS in acromegalic and growth hormone deficient patients

OBJECTIVES

Calibration is an important source of variability in liquid chromatography mass spectrometry (LC-MS) methods for insulin-like growth factor 1 (IGF-1). This study investigated the impact of different calibrator matrices on IGF-1 measurements by LC-MS. Moreover, the comparability of immunoassays and LC-MS was assessed.

DESIGN & METHODS

Calibrators from 12.5 to 2009 ng/ml were prepared by spiking WHO international Standard (ID 02/254 NIBSC, UK) into the following matrices: native human plasma, fresh charcoal-treated human plasma (FCTHP), old charcoal-treated human plasma, deionized water, bovine serum albumin (BSA), and rat plasma (RP). A validated in-house LC-MS method was calibrated repeatedly with these calibrators. Then, serum samples from 197 growth hormone excess and deficiency patients were analysed with each calibration.

RESULTS

The seven calibration curves had different slopes leading to markedly different patient results. The largest differences in IGF-1 concentration from the median (interquartile range) was observed with the calibrator in water and the calibrator in RP (336.4 [279.6-417.0] vs. 112.5 [71.2-171.2], p < 0.001). The smallest difference was observed with calibrators in FCTHP and BSA (141.8 [102.0-198.5] vs. 127.9 [86.9-186.0], p < 0.049). Compared to LC-MS with calibrators in FCTHP, immunoassays showed relevant proportional bias (range: -43% to -68%), constant bias (range: 22.84 to 57.29 ng/ml) and pronounced scatter. Comparing the immunoassays with each other revealed proportional bias of up to 24%.

CONCLUSIONS

The calibrator matrix is critical for the measurement of IGF-1 by LC-MS. Regardless of the calibrator matrix, LC-MS shows poor agreement with immunoassays. Also, the agreement between different immunoassays is variable.

Myostatin-mediated regulation of skeletal muscle damage post-acute Aeromonas hydrophila infection in Nile tilapia (Oreochromis niloticus L.)

This study focuses on the relationship between myostatin (MyoS), myogenin (MyoG), and the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis for muscle growth and histopathological changes in muscle after an Aeromonas hydrophila infection. A total number of 90 Nile tilapia (55.85 g) were randomly allocated into two equal groups of three replicates each. The first group was an uninfected control group that was injected intraperitoneally (ip) with 0.2 ml phosphate buffer saline (PBS), while the second group was injected ip with 0.2 ml (1.3 × 10⁸ CFU/ml) Aeromonas hydrophila culture suspension. Sections of white muscle and liver tissues were taken from each group 24 h, 48 h, 72 h, and 1 week after infection for molecular analysis and histopathological examination. The results revealed that with time progression, the severity of muscle lesions increased from edema between bundles and mononuclear inflammatory cell infiltration 24 h post-challenge to severe atrophy of muscle bundles with irregular and curved fibers with hyalinosis of the fibers 1 week postinfection. The molecular analysis showed that bacterial infection was able to induce the muscle expression levels of GH with reduced ILGF-1, MyoS, and MyoG at 24 h postinfection. However, time progression postinfection reversed these findings through elevated muscle expression levels of MyoS with regressed expression levels of muscle GH, ILGF-1, and MyoG. There have been no previous reports on the molecular expression analysis of the aforementioned genes and muscle histopathological changes in Nile tilapia following acute Aeromonas hydrophila infection. Our findings, collectively, revealed that the up-and down-regulation of the myostatin signaling is likely to be involved in the postinfection-induced muscle wasting through the negative regulation of genes involved in muscle growth, such as GH, ILGF-1, and myogenin, in response to acute Aeromonas hydrophila infection in Nile tilapia, Oreochromis niloticus.

IGF-Binding Proteins and Their Proteolysis as a Mechanism of Regulated IGF Release in the Nervous Tissue

Insulin-like growth factors 1 and 2 (IGF-1 and IGF-2) play a key role in the maintenance of the nervous tissue viability. IGF-1 and IGF-2 exhibit the neuroprotective effects by stimulating migration and proliferation of nervous cells, activating cellular metabolism, inducing regeneration of damaged cells, and regulating various stages of prenatal and postnatal development of the nervous system. The availability of IGFs for the cells is controlled via their interaction with the IGF-binding proteins (IGFBPs) that inhibit their activity. On the contrary, the cleavage of IGFBPs by specific proteases leads to the IGF release and activation of its cellular effects. The viability of neurons in the nervous tissue is controlled by a complex system of trophic factors secreted by auxiliary glial cells. The main source of IGF for the neurons are astrocytes. IGFs can accumulate as an extracellular free ligand near the neuronal membranes as a result of proteolytic degradation of IGFBPs by proteases secreted by astrocytes. This mechanism promotes interaction of IGFs with their genuine receptors and triggers intracellular signaling cascades. Therefore, the release of IGF by proteolytic cleavage of IGFBPs is an important mechanism of neuronal protection. This review summarizes the published data on the role of IGFs and IGFBPs as the key players in the neuroprotective regulation with a special focus on the specific proteolysis of IGFBPs as a mechanism for the regulation of IGF bioavailability and viability of neurons.

New insights on the cardiovascular effects of IGF-1

INTRODUCTION

Cardiovascular (CV) disorders are steadily increasing, making them the world's most prevalent health issue. New research highlights the importance of insulin-like growth factor 1 (IGF-1) for maintaining CV health.

METHODS

We searched PubMed and MEDLINE for English and non-English articles with English abstracts published between 1957 (when the first report on IGF-1 identification was published) and 2022. The top search terms were: IGF-1, cardiovascular disease, IGF-1 receptors, IGF-1 and microRNAs, therapeutic interventions with IGF-1, IGF-1 and diabetes, IGF-1 and cardiovascular disease. The search retrieved original peer-reviewed articles, which were further analyzed, focusing on the role of IGF-1 in pathophysiological conditions. We specifically focused on including the most recent findings published in the past five years.

RESULTS

IGF-1, an anabolic growth factor, regulates cell division, proliferation, and survival. In addition to its well-known growth-promoting and metabolic effects, there is mounting evidence that IGF-1 plays a specialized role in the complex activities that underpin CV function. IGF-1 promotes cardiac development and improves cardiac output, stroke volume, contractility, and ejection fraction. Furthermore, IGF-1 mediates many growth hormones (GH) actions. IGF-1 stimulates contractility and tissue remodeling in humans to improve heart function after myocardial infarction. IGF-1 also improves the lipid profile, lowers insulin levels, increases insulin sensitivity, and promotes glucose metabolism. These findings point to the intriguing medicinal potential of IGF-1. Human studies associate low serum levels of free or total IGF-1 with an increased risk of CV and cerebrovascular illness. Extensive human trials are being conducted to investigate the therapeutic efficacy and outcomes of IGF-1-related therapy.

DISCUSSION

We anticipate the development of novel IGF-1-related therapy with minimal side effects. This review discusses recent findings on the role of IGF-1 in the cardiovascular (CVD) system, including both normal and pathological conditions. We also discuss progress in therapeutic interventions aimed at targeting the IGF axis and provide insights into the epigenetic regulation of IGF-1 mediated by microRNAs.

The Effects of Prenatal and Postnatal Exposure to 50-Hz and 3 mT Electromagnetic Field on Rat Testicular Development

Background and objectives: It has been shown that electromagnetic fields (EMFs) have negative effects on the reproductive system. The biological effects of EMF on the male reproductive system are controversial and vary depending on the frequency and exposure time. Although a limited number of studies have focused on the structural and functional effects of EMF, the effects of prenatal and postnatal EMF exposure on testes are not clear. We aimed to investigate the effects of 50-Hz, 3-mT EMF exposure (5 days/wk, 4 h/day) during pre- and postnatal periods on testis development. Materials and Methods: Pups from three groups of Sprague-Dawley pregnant rats were used: Sham, EMF-28 (EMF-exposure applied during pregnancy and until postnatal day 28), EMF-42 (EMF-exposure applied during pregnancy and until postnatal day 42). The testis tissues and blood samples of male offspring were collected on the postnatal day 42. Results: Morphometric analyses showed a decrease in seminiferous tubule diameter as a result of testicular degeneration in the EMF-42 group. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were decreased in the EMF-42 group. Lipid peroxidation levels were increased in both EMF groups, while antioxidant levels were decreased only in the EMF-28 group. We found decreased levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF1) in the EMF-42 group, and decreased levels of the SRC homology 3 (SH3) and multiple ankyrin repeat domain (SHANK3) in the EMF-28 group in the testis tissue. Conclusions: EMF exposure during pre- and postnatal periods may cause deterioration in the structure and function of testis and decrease in growing factors that would affect testicular functions in male rat pups. In addition to the oxidative stress observed in testis, decreased SHANK3, VEGF, and IGF1 protein levels suggests that these proteins may be mediators in testis affected by EMF exposure. This study shows that EMF exposure during embryonic development and adolescence can cause apoptosis and structural changes in the testis.

IGF1 deficiency integrates stunted growth and neurodegeneration in Down syndrome

Down syndrome (DS), the genetic condition caused by trisomy 21 (T21), is characterized by stunted growth, cognitive impairment, and increased risk of diverse neurological conditions. Although signs of lifelong neurodegeneration are well documented in DS, the mechanisms underlying this phenotype await elucidation. Here we report a multi-omics analysis of neurodegeneration and neuroinflammation biomarkers, plasma proteomics, and immune profiling in a diverse cohort of more than 400 research participants. We identified depletion of insulin growth factor 1 (IGF1), a master regulator of growth and brain development, as the top biosignature associated with neurodegeneration in DS. Individuals with T21 display chronic IGF1 deficiency downstream of growth hormone production, associated with a specific inflammatory profile involving elevated tumor necrosis factor alpha (TNF-α). Shorter children with DS show stronger IGF1 deficiency, elevated biomarkers of neurodegeneration, and increased prevalence of autism and other conditions. These results point to disruption of IGF1 signaling as a potential contributor to stunted growth and neurodegeneration in DS.

Potential Role of Insulin-Like Growth Factors in Myofascial Pain Syndrome: A Narrative Review

ABSTRACT

Insulin-like growth factors have diverse functions in skeletal muscles by acting through multiple signaling pathways, including growth regulation and differentiation, anti-inflammation, and antioxidation. Insulin-like growth factors have anti-inflammatory effects and also play roles in nociceptive pathways, determining pain sensitivity, in addition to their protective role against ischemic injury in both the nervous system and skeletal muscle. In skeletal muscle, insulin-like growth factors maintain homeostasis, playing key roles in maintenance, accelerating muscle regeneration, and repair processes. As part of their maintenance role, increased levels of insulin-like growth factors may be required for the repair mechanisms after exercise. Although the role of insulin-like growth factors in myofascial pain syndrome is not completely understood, there is evidence from a recent study that insulin-like growth factor 2 levels in patients with myofascial pain syndrome are lower than those of healthy individuals and are associated with increased levels of inflammatory biomarkers. Importantly, higher insulin-like growth factor 2 levels are associated with increased pain severity in myofascial pain syndrome patients. This may suggest that too low or high insulin-like growth factor levels may contribute to musculoskeletal disorder process, whereas a midrange levels may optimize healing without contributing to pain hypersensitivity. Future studies are required to address the mechanisms of insulin-like growth factor 2 in myofascial pain syndrome and the optimal level as a therapeutic agent.

Preoperative Risk Stratification of Increased MIB-1 Labeling Index in Pituitary Adenoma: A Newly Proposed Prognostic Scoring System

The MIB-1 index is an important risk factor for progression-free survival (PFS) in pituitary adenoma (PA). Preoperatively, the MIB-1 index is not available in the decision-making process. A preoperative method regarding MIB-1 index estimation in PA has not been evaluated so far. Between 2011 and 2021, 109 patients with tumor morphology data, MIB-1 index data, and inflammatory and pituitary hormone laboratory values underwent surgery for PA. An MIB-1 index cutoff point (≥4/<4%) determines the probability of PFS in completely resected PA. An elevated MIB-1 index (≥4%) was present in 32 cases (29.4%) and was significantly associated with increased IGF-1, age ≤ 60, increased ACTH, and increased fibrinogen levels in the multivariable analysis. A scoring system (“FATE”) using preoperative IGF-1, age, ACTH, and plasma fibrinogen level enables the estimation of the MIB-1 index (sensitivity 72%, specificity 68%). The FATE score is also significantly associated with the time to PA progression after the complete resection of the PA. We propose the FATE score to preoperatively estimate the risk of an elevated MIB-1 index (≥4%), which might enable tailoring to medical decision-making, and follow-up interval scheduling, as well as inform future studies analyzing proliferative activities.

The effect of genistein on IGF-1, PlGF, sFLT-1 and fetoplacental development

The mechanisms by which genistein, a phytoestrogen, affects fetoplacental development adversely are still poorly understood. It is reported that genistein ingestion modulates thyroid functions, leptin hormone, C-reactive protein, and thyroxin kinase activities. In this study, we evaluated changes in serum and placental insulin-like growth factor-I (IGF-1), placental growth factor (PIGF), and soluble fms-like tyrosine kinase-1 (sFLT-1) in pregnant rats exposed to genistein using ELISA. According to the treatments, Rats were divided into control, 2 mg genistein, and 4 mg genistein groups. Genistein groups were administered with the doses orally from gestational day (GD) one onwards until sacrifice, while the control group received an equal volume of distilled water the vehicle. At GD-12, GD-16, and GD-20, serum samples and placenta homogenates were prepared from maternal blood samples and the placenta and were analysed to determine the concentration of IGF-1, sFLT-1, and PIGF. Serum IGF-1 and PIGF were both increased in all genistein groups at GD-12 and GD-16, and at GD-20 in the 4 mg group. However, serum IGF-1and PIGF levels were decreased in the placenta from all genistein groups at GD-20. Placenta sFLT-1 levels increased at both GD-16 and GD-20 in genistein-treated rat serum. An initial decrease in placental sFLT-1 at GD-12 was followed by an increase at GD-16 and finally a decrease at GD-20 in all genistein-treated rats. The sFL-1/PlGF ratio in placenta samples of genistein-exposed rats was decreased at GD-16 and increased at GD-20, while the reverse was recorded in the serum sample at the same gestational periods. The fetoplacental growth disruption mechanism of genistein can be partly explained by its interference with placental growth factor signalling.

Histopathologic evaluation of the inflammatory factors and stromal cells in the endometriosis lesions: A case-control study

Background

Endometriosis is a multifaceted gynecological disorder defined as a benign estrogen-dependent chronic inflammatory process in which endometrial glands and stroma-like tissues are located outside the uterine cavity. It affects around 2-10% of all women during their reproductive years.

Objective

This study aimed to evaluate the traffic of mesenchymal stem cells and inflammatory factors toward the lesions.

Materials and Methods

Ten samples of normal endometrium and eutopic endometrium were studied as a control group and 10 ectopic samples were considered as a case group. Hematoxylin and eosin staining was used to evaluate stromal cells and inflammatory cells. Immunohistochemical staining was performed to show the presence of proliferating cell nuclear antigen in the lesions. The cells were digested and cultured in the laboratory to study cell proliferation. The number of cells and vessels were counted with Image J software, and data analysis was performed with Prism software.

Results

Data analysis showed that the number of stromal cells and vessels in ectopic tissue were significantly higher than the control group (p < 0.001). Also, the number of inflammatory cells, including neutrophils, monocytes, lymphocytes, and macrophages, in the ectopic group was much higher than in the control group (p < 0.005).

Conclusion

By expanding the number of blood vessels, blood flow increases, and cell migration to tissues is facilitated. The accumulation of inflammatory cells, especially macrophages, stimulates the growth of stem cells and helps implant cells by creating an inflammatory process.

Copeptin in Growth Hormone-Treated Patients

Growth hormone (GH) changes body composition, including increasing body water. GH is known to have an anti-natriuretic effect in the kidney, but little is known of its effect on arginine-vasopressin (AVP) release. We studied the effect of GH on AVP release by measurement of copeptin, a fragment from the same precursor protein, in GH-treated patients with GH deficiency. The study was designed as a retrospective cohort study of biobank samples from 34 patients substituted with GH between 1999 and 2004. Copeptin and insulin-like growth factor 1 (IGF-1) results were compared with previously obtained data. An increase in IGF-1 and copeptin was seen at 3 and 6 months’ treatment compared to baseline. Between the 3 and 6 months follow up, copeptin levels were stable. There was a difference in HbA1c between 3 and 6 months (p < 0.01) and between baseline and 6 months (p = 0.042), with higher levels at 6 months. In addition, LDL levels were lower at the 6 months follow up (p = 0.046). The waist circumference at 3 months was lower (p = 0.02). To conclude, three months of GH treatment increased the levels of copeptin and the increase remained at 6 months. This could be a compensatory mechanism balancing the anti-natriuretic effect of GH treatment seen in previous studies.

Structure of the PAPP-ABP5 complex reveals mechanism of substrate recognition

Insulin-like growth factor (IGF) signaling is highly conserved and tightly regulated by proteases including Pregnancy-Associated Plasma Protein A (PAPP-A). PAPP-A and its paralog PAPP-A2 are metalloproteases that mediate IGF bioavailability through cleavage of IGF binding proteins (IGFBPs). Here, we present single-particle cryo-EM structures of the catalytically inactive mutant PAPP-A (E483A) in complex with a peptide from its substrate IGFBP5 (PAPP-ABP5) and also in its substrate-free form, by leveraging the power of AlphaFold to generate a high quality predicted model as a starting template. We show that PAPP-A is a flexible trans-dimer that binds IGFBP5 via a 25-amino acid anchor peptide which extends into the metalloprotease active site. This unique IGFBP5 anchor peptide that mediates the specific PAPP-A-IGFBP5 interaction is not found in other PAPP-A substrates. Additionally, we illustrate the critical role of the PAPP-A central domain as it mediates both IGFBP5 recognition and trans-dimerization. We further demonstrate that PAPP-A trans-dimer formation and distal inter-domain interactions are both required for efficient proteolysis of IGFBP4, but dispensable for IGFBP5 cleavage. Together the structural and biochemical studies reveal the mechanism of PAPP-A substrate binding and selectivity.

Potential role of IGF-1/GLP-1 signaling activation in intracerebral hemorrhage

IGF-1 and GLP-1 receptors are essential in all tissues, facilitating defense by upregulating anabolic processes. They are abundantly distributed throughout the central nervous system, promoting neuronal proliferation, survival, and differentiation. IGF-1/GLP-1 is a growth factor that stimulates neurons' development, reorganization, myelination, and survival. In primary and secondary brain injury, the IGF-1/GLP-1 receptors are impaired, resulting in further neuro complications such as cerebral tissue degradation, neuroinflammation, oxidative stress, and atrophy. Intracerebral hemorrhage (ICH) is a severe condition caused by a stroke for which there is currently no effective treatment. While some pre-clinical studies and medications are being developed as symptomatic therapies in clinical trials, there are specific pharmacological implications for improving post-operative conditions in patients with intensive treatment. Identifying the underlying molecular process and recognizing the worsening situation can assist researchers in developing effective therapeutic solutions to prevent post-hemorrhagic symptoms and the associated neural dysfunctions. As a result, in the current review, we have addressed the manifestations of the disease that are aggravated by the downregulation of IGF-1 and GLP-1 receptors, which can lead to ICH or other neurodegenerative disorders. Our review summarizes that IGF-1/GLP-1 activators may be useful for treating ICH and its related neurodegeneration.

Effect of Ethanol Consumption on the Placenta and Liver of Partially IGF-1-Deficient Mice: The Role of Metabolism via CYP2E1 and the Antioxidant Enzyme System

Simple Summary

Ethanol is the most consumed drug worldwide, even during pregnancy. One of its adverse outcomes is fetal growth restriction, an alteration in development due to decreased IGF-1 levels. Several studies have shown that ethanol can impair the IGF-1 signaling pathway, thus exacerbating IGF-1 adverse effects in both intrauterine and postnatal growth and development. In this manuscript, we used a partially IGF-1-deficient mouse model to demonstrate the key role of IGF-1 in fetal development, as well as ethanol’s adverse effects on CYP2E1 expression levels and the antioxidant enzyme system during pregnancy.

Abstract

Ethanol use during pregnancy is a risk factor for developing adverse outcomes. Its metabolism by cytochrome P450 2E1 (CYP2E1) produces radical oxygen species (ROS), promoting cellular injury and apoptosis. To date, no studies have been conducted to elucidate the teratogenic effects due to both IGF-1 deficiency and ethanol consumption in mice placentas. The aim of this study is to determine the effect of ethanol consumption on the placenta and liver of partially IGF-1-deficient mice, the role of metabolism via CYP2E1, and the antioxidant enzyme system. Heterozygous (HZ, Igf1^+/−) pregnant female mice were given water or 10% ethanol. Wild-type (WT, Igf1^+/+) female mice were used as controls. At gestational day 19, pregnant dams were euthanized, and maternal liver and placentas were collected. Pregnant HZ dams were smaller than controls, and this effect was higher due to ethanol consumption. Cyp2e1 gene was overexpressed in the liver of HZ pregnant dams exposed to ethanol; at the protein level, CYP2E1 is reduced in placentas from all genotypes. The antioxidant enzymatic system was altered by ethanol consumption in both the maternal liver and placenta. The results in this work hint that IGF-1 is involved in intrauterine development because its deficiency exacerbates ethanol’s effects on both metabolism and the placenta.

Chemical Bonding of Biomolecules to the Surface of Nano-Hydroxyapatite to Enhance Its Bioactivity

Hydroxyapatite (HA) is a significant constituent of bones or teeth and is widely used as an artificial bone graft. It is often used to replace the lost bones or in reconstructing alveolar bones before dental implantation. HA with biological functions finds its importance in orthopedic surgery and dentistry to increase the local concentration of calcium ions, which activate the growth and differentiation of mesenchymal stem cells (MSC). To make relevant use of HA in bone transplantation, the surfaces of orthopedic and dental implants are frequently coated with nanosized hydroxyapatite (nHA), but its low dispersibility and tendency to form aggregates, the purpose of the surface modification of bone implants is defeated. To overcome these drawbacks and to improve the histocompatibility of bone implants or to use nHA in therapeutic applications of implants in the treatment of bone diseases, various studies suggested the attachment of biomolecules (growth factors) or drugs through chemical bonding at the surface of nHA. The growth factors or drugs bonded physically at the surface of nHA are mostly unstable and burst released immediately. Therefore, reported studies suggested that the surface of nHA needs to be modified through the chemical bonding of biologically active molecules at the surface of bone implants such as proteins, peptides, or naturally occurring polysaccharides to prevent the aggregation of nHA and to get homogenous dispersion of nHA in solution. The role of irradiation in producing bioactive and antibacterial nHA through morphological variations in surfaces of nHA is also summarized by considering internal structures and the formation of reactive oxygen species on irradiation. This mini-review aims to highlight the importance of small molecules such as proteins, peptides, drugs, and photocatalysts in surface property modification of nHA to achieve stable, bioactive, and antibacterial nHA to act as artificial bone implants (scaffolds) in combination with biodegradable polymers.

Endocrine Autoantibodies Determine Immune Checkpoint Inhibitor-induced Endocrinopathy: A Prospective Study

CONTEXT

Incidence and awareness of endocrine-related adverse events (ERAE) associated with use of immune checkpoint inhibitors (ICI) has grown with increased ICI use, yet mechanisms for ERAE prediction, surveillance, and development are not well established.

OBJECTIVE

We prospectively evaluated the impact of endocrine autoimmunity on ERAE development and overall survival (OS).

METHODS

Adults ≥ 18 years of age prescribed ICI treatment for advanced or metastatic solid tumors and no known active/past endocrine disorders were eligible for enrollment. Thyroid, adrenal, and pancreatic antibodies as well as hormone levels were assessed prior to ICI treatment and at 8 to 9 weeks and 36 weeks after treatment for ERAE in relation to presence and changes in endocrine-specific antibodies, hormone levels, and OS.

RESULTS

Sixty patients were enrolled and ERAE were detected in 14 (23.3%), with a median onset of 52 days (IQR, 38.5-71.5) after first ICI dose. Hypothyroidism occurred in 12 (20%) patients, and 2 (3.33%) patients developed hypophysitis. Diabetes and primary adrenal insufficiency were not observed. Antibodies were detected in 14 patients (11 at baseline, 3 developed during follow-up) and their presence was significantly associated with ERAE (R2 59.3%, P < 0.001). Thyroid peroxidase antibody (20%) and thyroid-stimulating immunoglobulin (3.3%) were most common, and anti-GAD was present in 1 patient. The presence of ERAE was associated with a more favorable OS (P = 0.001).

CONCLUSION

Endocrine-specific autoantibodies play an important role in ERAE pathogenesis and may serve as predictive markers for early identification and treatment of ICI-induced endocrinopathies.

The drug-induced phenotypic landscape of colorectal cancer organoids

Patient-derived organoids resemble the biology of tissues and tumors, enabling ex vivo modeling of human diseases. They have heterogeneous morphologies with unclear biological causes and relationship to treatment response. Here, we use high-throughput, image-based profiling to quantify phenotypes of over 5 million individual colorectal cancer organoids after treatment with >500 small molecules. Integration of data using multi-omics modeling identifies axes of morphological variation across organoids: Organoid size is linked to IGF1 receptor signaling, and cystic vs. solid organoid architecture is associated with LGR5 + stemness. Treatment-induced organoid morphology reflects organoid viability, drug mechanism of action, and is biologically interpretable. Inhibition of MEK leads to cystic reorganization of organoids and increases expression of LGR5, while inhibition of mTOR induces IGF1 receptor signaling. In conclusion, we identify shared axes of variation for colorectal cancer organoid morphology, their underlying biological mechanisms, and pharmacological interventions with the ability to move organoids along them.

The heterogeneity underlying cancer organoid phenotypes is not yet well understood. Here, the authors develop an imaging analysis assay for high throughput phenotypic screening of colorectal organoids that allows to define specific morphological changes that occur following different drug treatments.

Targeting Insulin-Like Growth Factor-I in Management of Neurological Disorders

The degradation of neurons marks as the pathological reason for onset of most of the neurological diseases although the functional deficiencies and symptoms may vary. Insulin-like growth factor-I (IGF-I) boosts regeneration of both motor and sensory neurons and thus presents as a potential treatment in management of neurological disorders. IGF-I is a pleiotropic agent which stimulates the survival and outgrowth of neurons accompanied by their motility as well as myelination by glial cells. This hormone has been found to possess neuroprotective properties which is in association with its antioxidant and mitochondrial protection activity. Studying and exploring the signaling pathways which mediate pleotropic responses intracellularly have elucidated significant therapeutic approach in treatment and management of neurological disorders by IGF-I. The current review highlights the role of IGF-I in management of major neurological disorders such as depression, Parkinson's disease, and Alzheimer's disease and also covers the mechanisms involved in the process.

Declining Levels and Bioavailability of IGF-I in Cardiovascular Aging Associate With QT Prolongation-Results From the 1946 British Birth Cohort

Background

As people age, circulating levels of insulin-like growth factors (IGFs) and IGF binding protein 3 (IGFBP-3) decline. In rat cardiomyocytes, IGF-I has been shown to regulate sarcolemmal potassium channel activity and late sodium current thus impacting cardiac repolarization and the heart rate-corrected QT (QTc). However, the relationship between IGFs and IGFBP-3 with the QTc interval in humans, is unknown.

Objectives

To examine the association of IGFs and IGFBP-3 with QTc interval in an older age population-based cohort.

Methods

Participants were from the 1946 Medical Research Council (MRC) National Survey of Health and Development (NSHD) British birth cohort. Biomarkers from blood samples at age 53 and 60-64 years (y, exposures) included IGF-I/II, IGFBP-3, IGF-I/IGFBP-3 ratio and the change (Δ) in marker levels between the 60-64 and 53y sampled timepoints. QTc (outcome) was recorded from electrocardiograms at the 60-64y timepoint. Generalized linear multivariable models with adjustments for relevant demographic and clinical factors, were used for complete-cases and repeated after multiple imputation.

Results

One thousand four hundred forty-eight participants were included (48.3% men; QTc mean 414 ms interquartile range 26 ms). Univariate analysis revealed an association between low IGF-I and IGF-I/IGFBP-3 ratio at 60-64y with QTc prolongation [respectively: β -0.30 ms/nmol/L, (95% confidence intervals -0.44, -0.17), p < 0.001; β-28.9 ms/unit (-41.93, -15.50), p < 0.001], but not with IGF-II or IGFBP-3. No association with QTc was found for IGF biomarkers sampled at 53y, however both ΔIGF-I and ΔIGF-I/IGFBP-3 ratio were negatively associated with QTc [β -0.04 ms/nmol/L (-0.08, -0.008), p = 0.019; β -2.44 ms/unit (-4.17, -0.67), p = 0.007] while ΔIGF-II and ΔIGFBP-3 showed no association. In fully adjusted complete case and imputed models (reporting latter) low IGF-I and IGF-I/IGFBP-3 ratio at 60-64y [β -0.21 ms/nmol/L (-0.39, -0.04), p = 0.017; β -20.14 ms/unit (-36.28, -3.99), p = 0.015], steeper decline in ΔIGF-I [β -0.05 ms/nmol/L/10 years (-0.10, -0.002), p = 0.042] and shallower rise in ΔIGF-I/IGFBP-3 ratio over a decade [β -2.16 ms/unit/10 years (-4.23, -0.09), p = 0.041], were all independently associated with QTc prolongation. Independent associations with QTc were also confirmed for other previously known covariates: female sex [β 9.65 ms (6.65, 12.65), p < 0.001], increased left ventricular mass [β 0.04 ms/g (0.02, 0.06), p < 0.001] and blood potassium levels [β -5.70 ms/mmol/L (-10.23, -1.18) p = 0.014].

Conclusion

Over a decade, in an older age population-based cohort, declining levels and bioavailability of IGF-I associate with prolongation of the QTc interval. As QTc prolongation associates with increased risk for sudden death even in apparently healthy people, further research into the antiarrhythmic effects of IGF-I on cardiomyocytes is warranted.

Alteration of Porcine Intestinal Microbiota in Response to Dietary Manno-Oligosaccharide Supplementation

Manno-oligosaccharide (MOS) is a prebiotic derived from natural plants or yeasts. Here, we explored the response of intestinal microbiota and epithelial functions after ingestion of MOS in a porcine model. Sixteen pigs were randomly assigned into two treatments and fed with basal or MOS-containing (0.3% MOS) diet for 21 days. Results showed that MOS supplementation increased the cecal acetate content and ileal 16S rRNA gene copies (p < 0.05). Importantly, MOS decreased the abundance of phylum Proteobacteria in cecal digesta (p < 0.05). Moreover, MOS elevated the expression level of SCL5A8 and GPR109A but decreased the expression levels of HDAC1 and TNF-α in the ileal and cecal mucosa (p < 0.05). MOS upregulated the expression levels of tight-junction protein (ZO-1, claudin-1, and occludin) and IGF-1 in the ileum and cecum (p < 0.05). This study presents the alteration of intestinal microbiota composition and intestinal barrier function after MOS administration, and facilitates our understanding of the mechanisms behind the dietary MOS-modulated intestinal microbiota and health.

Macrophage-Specific IGF-1 Overexpression Reduces CXCL12 Chemokine Levels and Suppresses Atherosclerotic Burden in Apoe-Deficient Mice

OBJECTIVE

IGF-1 (insulin-like growth factor 1) exerts pleiotropic effects including promotion of cellular growth, differentiation, survival, and anabolism. We have shown that systemic IGF-1 administration reduced atherosclerosis in Apoe^-/- (apolipoprotein E deficient) mice, and this effect was associated with a reduction in lesional macrophages and a decreased number of foam cells in the plaque. Almost all cell types secrete IGF-1, but the effect of macrophage-derived IGF-1 on the pathogenesis of atherosclerosis is poorly understood. We hypothesized that macrophage-derived IGF-1 will reduce atherosclerosis. Approach and Results: We created macrophage-specific IGF-1 overexpressing mice on an Apoe^-/- background. Macrophage-specific IGF-1 overexpression reduced plaque macrophages, foam cells, and atherosclerotic burden and promoted features of stable atherosclerotic plaque. Macrophage-specific IGF1 mice had a reduction in monocyte infiltration into plaque, decreased expression of CXCL12 (CXC chemokine ligand 12), and upregulation of ABCA1 (ATP-binding cassette transporter 1), a cholesterol efflux regulator, in atherosclerotic plaque and in peritoneal macrophages. IGF-1 prevented oxidized lipid-induced CXCL12 upregulation and foam cell formation in cultured THP-1 macrophages and increased lipid efflux. We also found an increase in cholesterol efflux in macrophage-specific IGF1-derived peritoneal macrophages.

CONCLUSIONS

Macrophage IGF-1 overexpression reduced atherosclerotic burden and increased features of plaque stability, likely via a reduction in CXCL12-mediated monocyte recruitment and an increase in ABCA1-dependent macrophage lipid efflux.

Plasma microRNA-320a as a Potential Biomarker of Physiological Changes during Training in Professional Volleyball Players

A deeper insight into the mechanisms responsible for athlete performance that may serve as specific and detailed training indicators is still desired, because conventionally used biomarkers provide limited information about the adaptive processes that occur during exercise. The objective of our study was to assess insulin-like growth factor 1 receptors (IGF1R) gene expression and evaluate plasma concentration of selected microRNAs (miRNAs) during a 10-week training period (sampling times: week 1, 4, 7, and 10) in a group of 12 professional female volleyball players. Circulating miRNAs (miR-223, miR-320a, and miR-486) with established concentration in plasma and documented association with the IGF1 signaling pathway, which is involved in muscle development and recovery, were tested. The levels of analyzed miRNAs, tested by one-way ANOVA, were significantly different between four training periods during a 10-week training cycle (miR-223 p < 0.0001, miR-320a p = 0.00021, miR-486 p = 0.0037, respectively). The levels of IGF1R also appeared to be different (p = 0.00092), and their expression showed a trend to increase between the first and third periods. In the fourth period, the expression decreased, although it was higher compared with the baseline. Correlations between concentration levels of miR-223 and miR-320a (rs = 0.54, p < 0.001), as well as between miR-320a and miR-486 (rs = 0.73, p < 0.001) were also found. In the fourth period, a negative correlation between miR-223 plasma level and leucocyte IGF1R expression was found (rs = -0.63, p = 0.028). Multiple linear regression analysis showed that miR-320a (p = 0.024) and creatine kinase (p = 0.028) had the greatest impact on the expression levels of the IGF1R gene. Future studies are required to define whether these miRNAs, especially miR-320a, as well as IGF1R expression could be useful biomarkers of physiological changes during exercise and to discover their detailed biological roles in mode-specific exercise training adaptations of professional athletes.

Gestational Diabetes Mellitus and Energy-Dense Diet: What Is the Role of the Insulin/IGF Axis?

Gestational diabetes mellitus (GDM), is one of the most important pregnancy complications affecting approximately 15% of pregnant women. It is related to several gestational adverse outcomes in the fetus, e.g., macrosomia, shoulder dystocia, stillbirth, neonatal hypoglycemia, and respiratory distress. Women with GDM have a high risk of developing type 2 diabetes in the future. The pathogenesis of GDM is not completely understood; nevertheless, two factors could contribute to its development: β-cell dysfunction and failure in insulin secretion in response to insulin resistance induced by gestation. Both processes, together with the physiological activities of the insulin-like growth factors (IGFs), play a crucial role in glucose transport to the fetus and hence, fetal growth and development. IGFs (both IGF-1 and IGF-2) and their binding proteins (IGFBPs) regulate glucose metabolism and insulin sensitivity. Maternal nutritional status determines the health of the newborn, as it has substantial effects on fetal growth and development. Maternal obesity and an energy-dense diet can cause an increase in insulin and IGF-1 serum levels, producing metabolic disorders, such as insulin resistance, GDM, and high birth weight (> 4,000 g) due to a higher level of body fat. In this way, in GDM pregnancies there is an increase in IGF-1 and IGF-2 serum levels, and a decrease in IGFBP-1 and 4 serum levels, suggesting the crucial role of the insulin/IGF system in this gestational outcome. Here, the present review tries to elucidate the role that energy-dense diets and the insulin/IGF-1 signaling pathway perform in GDM pregnancies.

Hallmarks of exercised heart

The benefits of exercise in humans on the heart have been well recognized for many years. Long-term endurance exercise training can induce physiologic cardiac hypertrophy with normal or enhanced heart function, and provide protective benefits in preventing heart failure. The heart-specific responses that occur during exercise are complex and highly variable. This review mainly focuses on the current understanding of the structural and functional cardiac adaptations to exercise as well as molecular pathways and signaling proteins responsible for these changes. Here, we summarize eight tentative hallmarks that represent common denominators of the exercised heart. These hallmarks are: cardiomyocyte growth, cardiomyocyte fate reprogramming, angiogenesis and lymphangiogenesis, mitochondrial remodeling, epigenetic alteration, enhanced endothelial function, quiescent cardiac fibroblast, and improved cardiac metabolism. A major challenge is to explore the underlying molecular mechanisms for cardio-protective effects of exercise, and to identify therapeutic targets for heart diseases.

Maresin-1 Prevents Liver Fibrosis by Targeting Nrf2 and NF-κB, Reducing Oxidative Stress and Inflammation

Liver fibrosis is a complex process characterized by the excessive accumulation of extracellular matrix (ECM) and an alteration in liver architecture, as a result of most types of chronic liver diseases such as cirrhosis, hepatocellular carcinoma (HCC) and liver failure. Maresin-1 (MaR1) is derivative of ω-3 docosahexaenoic acid (DHA), which has been shown to have pro-resolutive and anti-inflammatory effects. We tested the hypothesis that the application of MaR1 could prevent the development of fibrosis in an animal model of chronic hepatic damage. Sprague-Dawley rats were induced with liver fibrosis by injections of diethylnitrosamine (DEN) and treated with or without MaR1 for four weeks. In the MaR1-treated animals, levels of AST and ALT were normalized in comparison with DEN alone, the hepatic architecture was improved, and inflammation and necrotic areas were reduced. Cell proliferation, assessed by the mitotic activity index and the expression of Ki-67, was increased in the MaR1-treated group. MaR1 attenuated liver fibrosis and oxidative stress was induced by DEN. Plasma levels of the pro-inflammatory mediators TNF-α and IL-1β were reduced in MaR1-treated animals, whereas the levels of IL-10, an anti-inflammatory cytokine, increased. Interestingly, MaR1 inhibited the translocation of the p65 subunit of NF-κB, while increasing the activation of Nrf2, a key regulator of the antioxidant response. Finally, MaR1 treatment reduced the levels of the pro-fibrotic mediator TGF-β and its receptor, while normalizing the hepatic levels of IGF-1, a proliferative agent. Taken together, these results suggest that MaR1 improves the parameters of DEN-induced liver fibrosis, activating hepatocyte proliferation and decreasing oxidative stress and inflammation. These results open the possibility of MaR1 as a potential therapeutic agent in fibrosis and other liver pathologies.

Association of decreased sperm motility and increased seminal plasma IGF-I, IGF-II, IGFBP-2, and PSA levels in infertile men

PURPOSE

Previous studies have suggested the involvement of serum insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in the regulation of the female reproductive system. Little is known of these peptides in the seminal plasma (SP) of men and their potential effects on fertility. We assessed SP levels of these peptides in infertile men with low sperm motility (asthenozoospermic; AZ) and low sperm counts (oligozoospermic; OZ), its effects on in vivo sperm motility, and whether there is a correlation with aging.

METHODS

Twenty-eight infertile men (AZ; n = 18 and OZ; n = 10) and 20 fertile normozoospermic (NZ) men were studied. Seminal plasma IGF-I, IGF-II, IGFBP-2, IGFBP-3, and prostate-specific antigen (PSA) levels were measured, and spermatozoa mRNA transcript patterns were examined.

RESULTS

Asthenozoospermic men had higher SP IGF-I, IGF-II, IGFBP-2, and PSA levels than NZ and OZ men, whereas SP IGFBP-3 levels were similar between the three groups. Sperm count positively correlated with SP IGF-I, IGF-II, and IGFBP-2; sperm motility negatively correlated with SP IGF-II and IGFBP-2; and age correlated positively with SP IGF-II. The expression of IGF-I and IGF-II mRNA and mRNA receptors was detectable, but no variations in transcript levels were noted.

CONCLUSION

Decreased sperm motility, but not sperm count, in infertile AZ men is associated with increased SP IGF-I, IGF-II, IGFBP-2, and PSA levels. Changes in SP IGFs and their interactions with IGFBPs and IGF receptors, and PSA levels suggest a role of these SP peptides in modulating sperm motility and possibly prostate disease development in aging men.

Protein Biomarkers in Glaucoma: A Review

Glaucoma is a multifactorial disease. Early diagnosis of this disease can support treatment and reduce the effects of pathophysiological processes. A significant problem in the diagnosis of glaucoma is limited access to the tested material. Therefore, intensive research is underway to develop biomarkers for fast, noninvasive, and reliable testing. Biomarkers indicated in the formation of glaucoma include chemical compounds from different chemical groups, such as proteins, sugars, and lipids. This review summarizes our knowledge about protein and/or their protein-like derived biomarkers used for glaucoma diagnosis since 2000. The described possibilities resulting from a biomarker search may contribute to identifying a group of compounds strongly correlated with glaucoma development. Such a find would be of great importance in the diagnosis and treatment of this disorder, as current screening techniques have low sensitivity and are unable to diagnose early primary open-angle glaucoma.

A Z-Linked E3 Ubiquitin Ligase Cs-rchy1 Is Involved in Gametogenesis in Chinese Tongue Sole, Cynoglossus semilaevis

Simple Summary

The sexual growth dimorphism prevails in animals and this phenomenon is even more obvious in marine fish, so understanding the mechanism of gonadal development and gametogenesis is of great importance for sex control, thus increased productivity in aquaculture. In mammal, ubiquitin ligase plays a versatile role in gonadal development and spermatogenesis, whereas its function in fish is little reported. Using Cynoglossus semilaevis (one-year-old female individual usually grows 2–4 times bigger than male) as the fish model, a Z-chromosome linked ubiquitin ligase neurl3 was previously identified and characterized, which suggested its involvement in spermatogenesis. However, in this study, characterization of another Z-chromosome linked ubiquitin ligase Cs-rchy1 suggested it might function both in spermatogenesis and oogenesis, as well as the potential role in growth. These data may provide the genetic resource for gene editing or marker exploration in future.

Abstract

Ubiquitin ligase (E3) plays a versatile role in gonadal development and spermatogenesis in mammals, while its function in fish is little reported. In this study, a Z-chromosome linked ubiquitin ligase rchy1 in C. semilaevis (Cs-rchy1) was cloned and characterized. The full-length cDNA was composed of 1962 bp, including 551 bp 5′UTR, 736 bp 3′UTR, and 675 bp ORF encoding a 224-amino-acid (aa) protein. Cs-rchy1 was examined among seven different tissues and found to be predominantly expressed in gonads. In testis, Cs-rchy1 could be detected from 40 days post hatching (dph) until 3 years post hatching (yph), but there was a significant increase at 6 months post hatching (mph). In comparison, the expression levels in ovary were rather stable among different developmental stages. In situ hybridization showed that Cs-rchy1 was mainly localized in germ cells, that is, spermatid and spermatozoa in testis and stage I, II and III oocytes in ovary. In vitro RNA interference found that Cs-rchy1 knockdown resulted in the decline of sox9 and igf1 in ovarian cell line and down-regulation of cyp19a in the testicular cell line. These data suggested that Cs-rchy1 might participate in gonadal differentiation and gametogenesis, via regulating steroid hormone synthesis.

Maternal Smoking During Pregnancy and Offspring Head Growth in Comparison to Height and Weight Growth Up to 6 Years of Age: A Longitudinal Study

Background

Maternal smoking during pregnancy causes fetal growth retardation. Thereafter, it has been associated with excessive childhood weight gain and decreased linear growth in the offspring. However, it is not known whether head circumference (HC), the surrogate of brain size in childhood, is altered after intrauterine tobacco exposure. We assessed the association of maternal smoking during pregnancy with offspring HC growth up to age 6 years in comparison with length/height growth and weight gain.

Methods

We combined data from Medical Birth Register and longitudinal growth data from primary care of 43,632 children (born 2004–2017). Linear mixed effects models were used for modeling, adjusting for potential perinatal and socioeconomic confounders.

Results

At birth, maternal smoking during pregnancy was associated with a mean deficit of 0.19 standard deviation score (SDS) (95% CI: −0.25, −0.12) in HC, −0.38 SDS (95% CI: −0.43, −0.32) in length, and −0.08 SDS (95% CI:−0.14, −0.02) in weight-for-length. HC in smokers’ children failed to catch up to that of non-smokers’ children. Height of smokers’ infants reached that of non-smokers’ infants by 12 months but declined thereafter. Weight-for-height of smokers’ infants exceeded the level of non-smokers’ infants at 3 months and remained significantly elevated thereafter. HC in the offspring of mothers who quit smoking in the first trimester was not deficient, but their weight-for-height was elevated.

Conclusion

HC of smokers’ children is still deficient at age 6 years. Since most of the head growth occurs during the first 2 years of life, the defect may be permanent. In smokers’ children, weight gain was excessive up to 6 years and height was deficient at 6 years consistent with previous literature. Efforts should be made to encourage pregnant women to quit smoking in the beginning of the pregnancy.

Oxidative-Signaling in Neural Stem Cell-Mediated Plasticity: Implications for Neurodegenerative Diseases

The adult mammalian brain is capable of generating new neurons from existing neural stem cells (NSCs) in a process called adult neurogenesis. This process, which is critical for sustaining cognition and mental health in the mature brain, can be severely hampered with ageing and different neurological disorders. Recently, it is believed that the beneficial effects of NSCs in the injured brain relies not only on their potential to differentiate and integrate into the preexisting network, but also on their secreted molecules. In fact, further insight into adult NSC function is being gained, pointing to these cells as powerful endogenous "factories" that produce and secrete a large range of bioactive molecules with therapeutic properties. Beyond anti-inflammatory, neurogenic and neurotrophic effects, NSC-derived secretome has antioxidant proprieties that prevent mitochondrial dysfunction and rescue recipient cells from oxidative damage. This is particularly important in neurodegenerative contexts, where oxidative stress and mitochondrial dysfunction play a significant role. In this review, we discuss the current knowledge and the therapeutic opportunities of NSC secretome for neurodegenerative diseases with a particular focus on mitochondria and its oxidative state.

IGF-I and NGFβ enhance in vitro progressive motility and vitality of human spermatozoa

PURPOSE

Progressive motility (PM) and vitality are positively associated with fertilization ability of spermatozoa. Here, the effects of IGF-I and NGFβ on PM and vitality of human spermatozoa were investigated.

METHODS

Forty-three volunteers gave semen samples after 2-3 days of sexual abstinence. Each sample was processed with density gradient centrifugation and sperm washing. The pellet was divided into 3 aliquots. An aliquot containing one million of progressively motile spermatozoa was incubated for an hour (37°C) in standard culture medium (control group), and two aliquots with the same number of progressively motile spermatozoa were incubated in medium supplemented with IGF-I or NGFβ. Two concentrations of IGF-I (100 ng/ml and 1000 ng/ml) and NGFβ (0,5 ng/ml and 5 ng/ml) were tested.

RESULTS

Both growth factors significantly increased PM and vitality in comparison with control either at the low or the high concentration. IGF-I seemed to be more effective than NGFβ. The effects did not seem to be dose dependent with the exception of the effect of IGF-I on vitality.

CONCLUSIONS

The enhancement of PM and vitality of human spermatozoa by IGF-I and NGFβ opens new ways for the improvement of sperm processing. Further research is needed to determine the most effective concentrations.