A simple cell proliferation assay and the inflammatory protein content show significant differences in human plasmas from young and old subjects.

Some studies showed a "rejuvenating" effect of exposing aging tissues to a young environment. In mouse heterochronic parabiosis experiments, in response to young organisms, old animals lived longer than isochrony old age-matched conjoint animals. Comparable "rejuvenating" effects were obtained by injecting young plasma in old mice. This raised great hopes of slowing down the senescence process in humans by the injection of young plasma, as well as to prevent or cure age-related diseases. Some clinical trials are currently being performed or were recently completed. However, these studies are small and of limited duration, and we still lack convincing evidence to support the effectiveness of young plasma injection. It is urgent to perform additional investigations, including the development of an assay to measure the cell proliferation induction capability of different human plasmas, before one can seriously think of a large-scale treatment of humans. We adopted a simple method to measure the potential of different plasmas in supporting cell line proliferation, regardless of the co-presence of a platelet lysate. By comparing plasmas from young and old subjects, we observed a decreased activity in plasmas from old individuals. The young plasma effect may be attributed to specific proteins and growth factors more abundant in younger individuals that could decrease with age. Alternatively, or at the same time, the reduced cell proliferation support could be due to inhibitors present in the old plasma. Studying the different protein content of young and old plasmas was out of the scope of this article. Such differences should be adequately investigated by proteomics using many samples. However, a preliminary study of the different protein content of young and old plasmas was part of the assay validation using a commercially available cytokine array for parallel determination of the relative levels of 105 selected human proteins. We could show the existence of specific differences between young and old plasmas and that plasmas from old individuals presented a higher concentration of "inflammatory" proteins.

Effect of Young Plasma Therapy on Cognition, Oxidative Stress, miRNA-134, BDNF, CREB, and SIRT-1 Expressions and Neuronal Survey in the Hippocampus of Aged Ovariectomized Rats with Alzheimer's.

Menopause may increase the risk of Alzheimer's disease (AD) dementia. This study aimed to use young plasma therapy (YPT) to improve dementia caused by AD in aged ovariectomized rats. Female Wistar rats were used in the following groups: (a) young (CY) (180-200 g, 2-3 months, n = 10) and (b) old groups (250-350 g, 22-24 months, n = 60). The old rats were randomly assigned to six sub-groups: (1) control, (2) sham, (3) ovariectomized group (OVX), (4) OVX + Alzheimer disease (OVX + AD), (5) OVX + AD+ 17ß-Estradiol (OVX + AD + E), and (6) OVX + AD + young plasma (OVX + AD + YP). Cognitive behaviors were evaluated using NOR, MWM, and PAL tests. MiR-134a, SIRT-1, CREB, and BDNF expressions were measured using real-time PCR and western blot, respectively. Oxidative stress in hippocampal tissue was assayed using ELISA kits. OVX and AD caused significant cognitive impairment (p < 0.001), up-regulated miR-134a (p < 0.001), down-regulated SIRT-1, CREB, and BDNF protein expression (p < 0.001), and decreased antioxidant marker levels (p < 0.001) compared to the sham group. YPT significantly restored miR-134a (p < 0.001), SIRT-1 (p < 0.001), CREB (p < 0.001), and BDNF (p < 0.001) protein expression in OVX + AD rats. YPT, as much as or more than estrogen therapy (ERT), significantly improved oxidative stress and down-regulated miR-134a expression and the up-regulation of SIRT-1, CREB, and BDNF proteins in OVX + AD rats (p < 0.001). YPT significantly improved histological alteration compared to the OVX + AD group (p < 0.001). As a non-pharmacological treatment, YPT can improve the expression of miR-134a and SIRT-1, CREB, and BDNF proteins as much as or more than estrogen therapy, ameliorating AD-induced dementia in aged OVX rats.

Chronic stress-induced anxiety-like behavior, hippocampal oxidative, and endoplasmic reticulum stress are reversed by young plasma transfusion in aged adult rats.

Objectives: Aging and stress synergistically induce behavioral dysfunctions associated with oxidative and endoplasmic reticulum (ER) stress in brain regions. Considering the rejuvenating effects of young plasma on aging brain function, in the current study, we examined the effects of young plasma administration on anxiety-like behavior, NADH oxidase, NADPH oxidase, and ER stress markers in the hippocampus of old male rats. Materials and Methods: Young (3 months old) and aged (22 months old) rats were randomly assigned into five groups: young control (Y), aged control (A), aged rats subjected to chronic stress for four weeks (A+S), aged rats subjected to chronic stress and treated with old plasma (A+S+OP), and aged rats subjected to chronic stress and treated with young plasma (A+S+YP). Systemic injection of (1 ml) young and old plasma was performed for four weeks (3 times/week). Results: Young plasma transfusion significantly improved anxiety-like behavior in aged rats and modulated oxidative stress in the hippocampus, evidenced by the increased NADH oxidase (NOX) activity and the reduced NADPH oxidase. In addition, the levels of C/EBP homologous protein (CHOP) and Glucose-Regulated Protein 78 (GRP-78), as ER stress markers, markedly reduced in the hippocampus following the administration of young plasma. Conclusion: These findings suggest that young plasma transfusion could reverse anxiety-like behavior in stress-exposed aged rats by modulating the hippocampal oxidative and ER stress markers.

Aging and age-related diseases with a focus on therapeutic potentials of young blood/plasma.

Aging is accompanied by alterations in the body with time-related to decline of physiological integrity and functionality process, responsible for increasing diseases and vulnerability to death. Several ages associated with biomarkers were observed in red blood cells, and consequently plasma proteins have a critical rejuvenating role in the aging process and age-related disorders. Advanced age is a risk factor for a broad spectrum of diseases and disorders such as cardiovascular diseases, musculoskeletal disorders and liver, chronic kidney disease, neurodegenerative diseases, and cancer because of loss of regenerative capacity, correlated to reduced systemic factors and raise of pro-inflammatory cytokines. Most studies have shown that systemic factors in young blood/plasma can strongly protect against age-related diseases in various tissues by restoring autophagy, increasing neurogenesis, and reducing oxidative stress, inflammation, and apoptosis. Here, we focus on the current advances in using young plasma or blood to combat aging and age-related diseases and summarize the experimental and clinical evidence supporting this approach. Based on reports, young plasma or blood is new a therapeutic approach to aging and age-associated diseases.

Young plasma reverses anesthesia and surgery-induced cognitive impairment in aged rats by modulating hippocampal synaptic plasticity.

We investigated the protective effect of young plasma on anesthesia- and surgery-induced cognitive impairment and the potential underlying mechanism using bioinformatics, functional enrichment analysis, gene set enrichment analysis, Golgi-Cox staining, dendritic spine analysis, immunofluorescence assay, western blot analysis, and transmission electron microscopy. Furthermore, we performed behavioral assessments using the open field test, the novel object recognition test, and the Morris water maze test. We identified 1969 differentially expressed genes induced by young plasma treatment, including 800 upregulated genes and 1169 downregulated genes, highlighting several enriched biological processes (signal release from synapse, postsynaptic density and neuron to neuron synapse). Anesthesia- and surgery-induced cognitive impairment in aged rats was comparatively less severe following young plasma preinfusion. In addition, the decreased levels of synapse-related and tyrosine kinase B/extracellular signal-regulated protein kinase/cyclic adenosine monophosphate response element-binding protein (TrkB/ERK/CREB) signaling pathway-related proteins, dendritic and spine deficits, and ultrastructural changes were ameliorated in aged mice following young plasma preinfusion. Together, these findings suggest that young plasma reverses anesthesia- and surgery-induced cognitive impairment in aged rats and that the mechanism is associated with the activation of the TrkB/ERK/CREB signaling pathway and improvement in hippocampal synaptic plasticity.

Umbilical cord plasma concentrate has beneficial effects on DNA methylation GrimAge and human clinical biomarkers.

Plasma transfusions are standard treatments to replace missing proteins in people with rare genetic diseases. Prior studies have demonstrated that heterochronic parabiosis has beneficial effects on several tissues of old animals receiving young blood. Human clinical trials are currently underway to investigate whether the infusion of plasma or plasma-derived factors from young donors can be used to mitigate human age-related conditions. Here, we use data from a safety study (n = 18, mean age 74) to investigate whether human umbilical cord plasma concentrate (hereinafter Plasma Concentrate) injected weekly (1 ml intramuscular) into elderly human subjects over a 10-week period affects different biomarkers, including epigenetic age measures, standard clinical biomarkers of organ dysfunction, mitochondrial DNA copy number (mtDNA-CN), and leukocyte telomere length. This study shows that treatment with plasma concentrate is safe. More than 20 clinical biomarkers were significantly and beneficially altered following the treatments. For example, creatinine was significantly decreased (p = 0.0039), while estimated glomerular filtration rate (eGFR) was increased (p = 0.0044), indicating the treatment may improve biomarkers of kidney function. Three of four immunoglobulin biomarkers decreased, while telomere length and mtDNA-CN were not significantly affected by the treatment. The treatment reduced DNA methylation-based GrimAge by an average of 0.82 years (p = 0.0093), suggests a reduction in morbidity and mortality risk. By contrast, no significant results could be observed for epigenetic clocks that estimate chronological age. Our results support the view that plasma concentrate contains youth-promoting factors.

Young Plasma Induces Antidepressant-Like Effects in Aged Rats Subjected to Chronic Mild Stress by Suppressing Indoleamine 2,3-Dioxygenase Enzyme and Kynurenine Pathway in the Prefrontal Cortex.

Pathophysiology of depression in elderlies is linked to aging-associated increase in indoleamine 2,3-dioxygenase (IDO) levels and activity and kynurenine (Kyn) metabolites. Moreover, these aging-induced changes may alter the brain's responses to stress. Growing evidence suggested that young plasma can positively affect brain dysfunctions in old age. The present study aimed to investigate whether the antidepressant effects of young plasma administration in aged rats subjected to chronic unpredictable mild stress (CUMS) and underlying mechanisms, focusing on the prefrontal cortex (PFC). Young (3 months old) and aged (22 months old) male rats were divided into five groups; young control, aged control, aged rats subjected to CUMS (A + CUMS), aged rats subjected to CUMS and treated with young plasma (A + CUMS + YP), and aged rats subjected to CUMS and treated with old plasma (A + CUMS + OP). Plasma was injected (1 ml, intravenously) three times per week for four weeks. Young plasma significantly improved CUMS-induced depressive-like behaviors, evidenced by the increased sucrose consumption ratio in the sucrose preference test and the reduced immobility time in the forced swimming test. Furthermore, young plasma markedly reduced the levels of interferon-gamma (IFN-γ), IDO, Kyn, and Kyn to tryptophan (Kyn/Trp) ratio in PFC tissue. Expression levels of the serotonin transporter and growth-associated protein (GAP)-43 were also significantly increased after chronic administration of young plasma. These findings provide evidence for the antidepressant effect of young plasma in old age; however, whether it improves depressive behaviors or faster recovery from stress-induced deficits is required to be elucidated.

Young plasma administration mitigates depression-like behaviours in chronic mild stress-exposed aged rats by attenuating apoptosis in prefrontal cortex.

NEW FINDINGS: What is the central question of this study? Young plasma contains several rejuvenating factors that exert beneficial effects in ageing and neurodegenerative diseases: can repeated transfusion of young plasma improve depressive behaviour in aged rats? What is the main finding and its importance? Following chronic transfusion of young plasma, depressive behaviour was improved in the depression model of aged rats, which was associated with reduced apoptosis process in the prefrontal cortex. ABSTRACT: Brain ageing alters brain responses to stress, playing an essential role in the pathophysiology of late-life depression. Moreover, apoptotic activity is up-regulated in the prefrontal cortex in ageing and stress-related mood disorders. Considerable evidence suggests that factors in young blood could reverse age-related dysfunctions in organs, especially in the brain. Therefore, this study investigated the effect of young plasma administration on depressive behaviours in aged rats exposed to chronic unpredictable mild stress (CUMS), with a focus on the apoptosis process. Young (3 months old) and aged (22 months old) male rats were randomly assigned into four groups: young control (YC), aged control (AC), aged rats subjected to CUMS (A+CUMS) and aged rats subjected to CUMS and treated with young plasma (A+CUMS+YP). In the A+CUMS and A+CUMS+YP groups, CUMS was used to generate the depression rat model. Moreover, the A+CUMS+YP group received pooled plasma (1 ml, intravenously), collected from young rats, three times per week for 4 weeks. Young plasma administration significantly improved CUMS-induced depression-like behaviours, including decreased sucrose consumption ratio, reduced locomotor activity and prolonged immobility time. Importantly, young plasma reduced neuronal apoptosis in the prefrontal cortex that was associated with reduced TUNEL-positive cells and cleaved caspase-3 protein levels in the A+CUMS+YP compared with the A+CUMS group. Young plasma can partially improve the neuropathology of late-life depression through the apoptotic signalling pathways.

Young plasma attenuates cognitive impairment and the cortical hemorrhage area in cerebral amyloid angiopathy model mice.

BACKGROUND: Cerebral amyloid angiopathy (CAA) is characterized by the deposition of ß-amyloid (Aß) in leptomeningeal vessels and penetrating arterioles. Intracerebral hemorrhage (ICH) is one of the most destructive complications in CAA. Young plasma has been shown to improve cognitive, learning, and memory functions in Alzheimer's disease (AD) model mice and is a new potential therapy. However, it is not clear whether young plasma can reduce cerebral hemorrhage and improve the prognosis of neurological function in APP/PS1 (which express APP695swe and PS1-dE9 mutations) mice with CAA disease. METHODS: The Y-maze, new object recognition (NOR), forced swimming, open field, sucrose consumption, and corner tests were used to evaluate the learning and memory, cognitive ability, and emotional changes in CAA model mice. The effect of young plasma on neurogenesis was analyzed by immunofluorescence. The level of Aß in the cerebral cortex and hippocampus of mice was measured by enzyme-linked immunosorbent assay (ELISA). Finally, the area of cortical hemorrhage in mice was analyzed by fast blue-staining. RESULTS: We proved that young plasma improved cognition, learning and memory impairment, and anxiety in CAA model mice, prevented neuronal apoptosis, and enhanced neurogenesis in APP/PS1 mice. However, young plasma did not reduce the level of Aß in the cortex and hippocampus of APP/PS1 mice. We also found that young plasma reduced the area of cerebral hemorrhage in APP/PS1 mice. CONCLUSIONS: Our results show that young plasma can improve learning and memory, cognitive impairment, and anxiety in CAA model mice and can reduce the area of cortical hemorrhage.

Safety of Plasma Infusions in Parkinson's Disease.

BACKGROUND: Young plasma infusions have emerged as a potential treatment for neurodegenerative disease, and convalescent plasma therapy has been used safely in the management of viral pandemics. However, the effect of plasma therapy in Parkinson's disease (PD) is unknown. OBJECTIVES: The objective of this study was to determine the safety, tolerability, and feasibility of plasma infusions in people with PD. METHODS: A total of 15 people with clinically established PD, at least 1 cognitive complaint, and on stable therapy received 1 unit of young fresh frozen plasma twice a week for 4 weeks. Assessments and adverse effects were performed/reported on and off therapy at baseline, immediately after, and 4 weeks after the infusions ended. Adverse effects were also assessed during infusions. The primary outcomes were safety, tolerability, and feasibility. Exploratory outcomes included Unified Parkinson's Disease Rating Scale Part III off medication, neuropsychological battery, Parkinson's Disease Questionnaire-39, inflammatory markers (tumor necrosis factor-α, interleukin-6), uric acid, and quantitative kinematics. RESULTS: Adherence rate was 100% with no serious adverse effects. There was evidence of improvement in phonemic fluency (P = 0.002) and in the Parkinson's Disease Questionnaire-39 stigma subscore (P = 0.013) that were maintained at the delayed evaluation. Elevated baseline tumor necrosis factor-α levels decreased 4 weeks after the infusions ended. CONCLUSIONS: Young fresh frozen plasma was safe, feasible, and well tolerated in people with PD, without serious adverse effects and with preliminary evidence for improvements in phonemic fluency and stigma. The results of this study warrant further therapeutic investigations in PD and provide safety and feasibility data for plasma therapy in people with PD who may be at higher risk for severe complications of COVID-19. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Open-Label Phase 1 Futility Studies of Salsalate and Young Plasma in Progressive Supranuclear Palsy.

BACKGROUND: Progressive supranuclear palsy (PSP) is a neurodegenerative disease without approved therapies, and therapeutics are often tried off-label in the hope of slowing disease progression. Results from these experiences are seldom shared, which limits evidence-based knowledge to guide future treatment decisions. OBJECTIVES: To describe an open-label experience, including safety/tolerability, and longitudinal changes in biomarkers of disease progression in PSP-Richardson's syndrome (PSP-RS) patients treated with either salsalate or young plasma and compare to natural history data from previous multicenter studies. METHODS: For 6 months, 10 PSP-RS patients received daily salsalate 2,250 mg, and 5 patients received monthly infusions of four units of young plasma. Every 3 months, clinical severity was assessed with the Progressive Supranuclear Palsy Rating Scale (PSPRS), and MRI was obtained for volumetric measurement of midbrain. A range of exploratory biomarkers, including cerebrospinal fluid levels of neurofilament light chain, were collected at baseline and 6 months. Interventional data were compared to historical PSP-RS patients from the davunetide clinical trial and the 4-Repeat Tauopathy Neuroimaging Initiative. RESULTS: Salsalate and young plasma were safe and well tolerated. PSPRS change from baseline (mean ± standard deviation [SD]) was similar in salsalate (+5.6 ± 9.6), young plasma (+5.0 ± 7.1), and historical controls (+5.6 ± 7.1), and change in midbrain volume (cm3 ± SD) did not differ between salsalate (-0.07 ± 0.03), young plasma (-0.06 ± 0.03), and historical controls (-0.06 ± 0.04). No differences were observed between groups on any exploratory endpoint. CONCLUSIONS: Neither salsalate nor young plasma had a detectable effect on disease progression in PSP-RS. Focused open-label clinical trials incorporating historical clinical, neuropsychological, fluid, and imaging biomarkers provide useful preliminary data about the promise of novel PSP-directed therapies.

Infusion of Plasma from Exercised Mice Ameliorates Cognitive Dysfunction by Increasing Hippocampal Neuroplasticity and Mitochondrial Functions in 3xTg-AD Mice.

Alzheimer's disease is the most common neurodegenerative brain disease causing dementia. It is characterized by slow onset and gradual worsening of memory and other cognitive functions. Recently, parabiosis and infusion of plasma from young mice have been proposed to have positive effects in aging and Alzheimer's disease. Therefore, this study examined whether infusion of plasma from exercised mice improved cognitive functions related to the hippocampus in a 3xTg-Alzheimer's disease (AD) model. We collected plasma from young mice that had exercised for 3 months and injected 100 µL of plasma into the tail vein of 12-month-old 3xTg-AD mice 10 times at 3-day intervals. We then analyzed spatial learning and memory, long-term memory, hippocampal GSK3ß/tau proteins, synaptic proteins, mitochondrial function, apoptosis, and neurogenesis. In the hippocampus of 3xTg-AD mice, infusion of plasma from exercised mice improved neuroplasticity and mitochondrial function and suppressed apoptosis, ultimately improving cognitive function. However, there was no improvement in tau hyperphosphorylation. This study showed that plasma from exercised mice could have a protective effect on cognitive dysfunction and neural circuits associated with AD via a tau-independent mechanism involving elevated brain-derived neurotrophic factor due to exercise.

Young plasma ameliorates aging-related acute brain injury after intracerebral hemorrhage.

Aging has been shown to contribute to both the declined biofunctions of aging brain and aggravation of acute brain damage, and the former could be reversed by young plasma. These results suggest that young plasma treatment may also reduce the acute brain damage induced by intracerebral hemorrhage (ICH). In the present study, we first found that the administration of young plasma significantly reduced the mortality and neurological deficit score in aging ICH rodents, which might be due to the decreased brain water content, damaged neural cells, and increased survival neurons around the perihematomal brain tissues. Then, proteomics analysis was used to screen out the potential neuroprotective circulating factors and the results showed that many factors were changed in health human plasma among young, adult, and old population. Among these significantly changed factors, the plasma insulin-like growth factor 1 (IGF-1) level was significantly decreased with age, which was further confirmed both in human and rats detected by ELISA. Additionally, the brain IGF-1 protein level in aging ICH rats was markedly decreased when compared with young rats. Interestingly, the relative decreased brain IGF-1 level was reversed by the treatment of young plasma in aging ICH rats, while the mRNA level was non-significantly changed. Furthermore, the IGF-1 administration significantly ameliorated the acute brain injury in aging ICH rats. These results indicated that young circulating factors, like IGF-1, may enter brain tissues to exert neuroprotective effects, and young plasma may be considered as a novel therapeutic approach for the clinical treatment of aging-related acute brain injury.

Blood-Based Therapies to Combat Aging.

Dysfunction associated with the aging process positions aging as a leading culprit for development of devastating diseases and mounting health-care costs. Many age-associated conditions for which aging increases risk are neurological disorders with no effective treatments, including Alzhei-mer's disease. As the proportion of aged individuals continues to rise in the coming decades, aging-related costs are expected to increase dramatically. Diverse approaches have emerged to meet the clinical need to treat aging and its associated conditions, including those aimed at increasing longevity, slowing the aging process itself, and improving healthspan. An emerging approach takes advantage of molecules circulating in the blood to limit or reverse aspects of aging in various organs throughout the body. Efforts are underway to translate these findings into novel therapeutics that harness the activity of youth-associated molecules present within blood. Here, we discuss the current state of blood-based approaches in this arena. Despite the apparent ease with which blood products might conceivably be applied as treatment paradigms, we propose that challenges nonetheless exist, which may be overcome with mechanistic studies that identify common pathways for targeted therapeutics.

Young Blood Plasma Administration to Fight Alzheimer's Disease?

Despite decades of intensive research, no drugs can cure or even stabilize Alzheimer's disease (AD). Current pharmacological treatments only partially mask the symptoms while the disease progresses within the brain. Finding a preventive measure or a cure for people with AD is indeed a worldwide urgent priority. A recent interesting study by T. Wyss-Coray's research group provides the first evidence that exposure to young blood or plasma can reverse some AD-related molecular and behavioral alterations. Heterochronic parabiosis (shared blood circulation) of AD transgenic mice with young healthy mice did not reduce amyloidosis and microglial activation in AD mice, but reversed the loss of synaptophysin and calbindin (critical synaptic proteins, indicators of cognitive decline in AD) in the dentate gyrus, and the abnormal expression, in the hippocampus, of many genes involved in key neuronal signaling pathways. Moreover, repeated intravenous administration of plasma from young healthy mice to AD mice reversed the excessive phosphorylation of hippocampal extracellular signal-regulated kinase (ERK), and improved spatial working memory and associative memory. Although observations in mouse models of AD might not necessarily extrapolate to humans, this preclinical study provides the first demonstration that young plasma has potential therapeutic properties, by ameliorating aspects of the disease that are present in AD patients. Clinical trials are already under way. If young plasma transfusion will be effective in AD patients, it will be important to identify the key factors responsible for the positive effects, as they might lead to the development of molecule interventions with a better efficacy/risk profile.

Geroscience: Addressing the mismatch between its exciting research opportunities, its economic imperative and its current funding crisis.

There is at present a huge disconnect between levels of funding for basic research on fundamental mechanisms of biological aging and, given demographic projections, the anticipated enormous social and economic impacts of a litany of chronic diseases for which aging is by far the major risk factor: One valuable approach, recently instigated by Felipe Sierra & colleagues at the US National Institute on Aging, is the development of a Geroscience Interest Group among virtually all of the NIH institutes. A complementary approach would be to seek major escalations of private funding. The American Federation for Aging Research, the Paul Glenn Foundation and the Ellison Medical Foundation pioneered efforts by the private sector to provide substantial supplements to public sources of funding. It is time for our community to organize efforts towards the enhancements of such crucial contributions, especially in support of the emerging generation of young investigators, many of whom are leaving our ranks to seek alternative employment. To do so, we must provide potential donors with strong economic, humanitarian and scientific rationales. An initial approach to such efforts is briefly outlined in this manuscript as a basis for wider discussions within our community.