scholarly journals Models of Distal Arthrogryposis and Lethal Congenital Contracture Syndrome

Genes ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 943
Author(s):  
Julia Whittle ◽  
Aaron Johnson ◽  
Matthew B. Dobbs ◽  
Christina A. Gurnett

Distal arthrogryposis and lethal congenital contracture syndromes describe a broad group of disorders that share congenital limb contractures in common. While skeletal muscle sarcomeric genes comprise many of the first genes identified for Distal Arthrogyposis, other mechanisms of disease have been demonstrated, including key effects on peripheral nerve function. While Distal Arthrogryposis and Lethal Congenital Contracture Syndromes display superficial similarities in phenotype, the underlying mechanisms for these conditions are diverse but overlapping. In this review, we discuss the important insights gained into these human genetic diseases resulting from in vitro molecular studies and in vivo models in fruit fly, zebrafish, and mice.

2018 ◽  
Vol 115 (30) ◽  
pp. 7813-7818 ◽  
Author(s):  
Iryna Prots ◽  
Janina Grosch ◽  
Razvan-Marius Brazdis ◽  
Katrin Simmnacher ◽  
Vanesa Veber ◽  
...  

α-Synuclein (α-Syn) aggregation, proceeding from oligomers to fibrils, is one central hallmark of neurodegeneration in synucleinopathies. α-Syn oligomers are toxic by triggering neurodegenerative processes in in vitro and in vivo models. However, the precise contribution of α-Syn oligomers to neurite pathology in human neurons and the underlying mechanisms remain unclear. Here, we demonstrate the formation of oligomeric α-Syn intermediates and reduced axonal mitochondrial transport in human neurons derived from induced pluripotent stem cells (iPSC) from a Parkinson’s disease patient carrying an α-Syn gene duplication. We further show that increased levels of α-Syn oligomers disrupt axonal integrity in human neurons. We apply an α-Syn oligomerization model by expressing α-Syn oligomer-forming mutants (E46K and E57K) and wild-type α-Syn in human iPSC-derived neurons. Pronounced α-Syn oligomerization led to impaired anterograde axonal transport of mitochondria, which can be restored by the inhibition of α-Syn oligomer formation. Furthermore, α-Syn oligomers were associated with a subcellular relocation of transport-regulating proteins Miro1, KLC1, and Tau as well as reduced ATP levels, underlying axonal transport deficits. Consequently, reduced axonal density and structural synaptic degeneration were observed in human neurons in the presence of high levels of α-Syn oligomers. Together, increased dosage of α-Syn resulting in α-Syn oligomerization causes axonal transport disruption and energy deficits, leading to synapse loss in human neurons. This study identifies α-Syn oligomers as the critical species triggering early axonal dysfunction in synucleinopathies.


2021 ◽  
Author(s):  
◽  
Tanisha Vithal

<p>Alzheimer’s disease (AD) is a neurodegenerative disease that is responsible for 50-80% of dementia cases and is characterised by lack of visuospatial perception, impairment of language and memory. One of the main physiological attributions towards this disease is the accumulation of large insoluble deposits of amyloid beta, a toxic peptide, which results in the generation of amyloid plaques found in between neurons in the brain. Currently no therapeutic treatments are available. Clusterin (CLU) is an apolipoprotein that when defective is the second highest genetic risk factor for AD. It has been strongly debated whether CLU counteracts or promotes AD pathology. With the roles of CLU including but not limited to acting as a chaperone for cholesterol transport and aiding autophagy functionality in cancer models, this thesis investigates these two specific functionalities by overexpressing CLU in an in vitro SH-SY5Y and in an in vivo AD model of Drosophila melanogaster (fruit fly). Conclusions from this study reveal that within D. melanogaster, CLU reduced Aβ42 levels and increased cholesterol effect through the blood brain barrier. Additionally, in human cells, CLU ameliorated the defective flux in autophagy. This thesis sheds light into how CLU plays a protective role within an Alzheimer’s disease mammalian system.</p>


Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 748
Author(s):  
Moritz Pfeiffenberger ◽  
Alexandra Damerau ◽  
Annemarie Lang ◽  
Frank Buttgereit ◽  
Paula Hoff ◽  
...  

Fractures are one of the most frequently occurring traumatic events worldwide. Approximately 10% of fractures lead to bone healing disorders, resulting in strain for affected patients and enormous costs for society. In order to shed light into underlying mechanisms of bone regeneration (habitual or disturbed), and to develop new therapeutic strategies, various in vivo, ex vivo and in vitro models can be applied. Undeniably, in vivo models include the systemic and biological situation. However, transferability towards the human patient along with ethical concerns regarding in vivo models have to be considered. Fostered by enormous technical improvements, such as bioreactors, on-a-chip-technologies and bone tissue engineering, sophisticated in vitro models are of rising interest. These models offer the possibility to use human cells from individual donors, complex cell systems and 3D models, therefore bridging the transferability gap, providing a platform for the introduction of personalized precision medicine and finally sparing animals. Facing diverse processes during fracture healing and thus various scientific opportunities, the reliability of results oftentimes depends on the choice of an appropriate model. Hence, we here focus on categorizing available models with respect to the requirements of the scientific approach.


Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 875 ◽  
Author(s):  
Chao Zhang ◽  
Chaoying Li ◽  
Xuejing Jia ◽  
Kai Wang ◽  
Yanbei Tu ◽  
...  

Background: Polyphyllin VII (PP7), a steroidal saponin from Paris polyphylla, has been found to exert strong anticancer activity. Little is known about the anti-inflammatory property of PP7. In this study, the anti-inflammatory activity and its underlying mechanisms of PP7 were evaluated in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and in multiple animal models. Methods: The content of nitric oxide (NO) was determined by spectrophotometry. The levels of prostaglandin E2 (PGE2) and cytokines were measured by enzyme-linked immunosorbent assay (ELISA) assay. The mRNA expression of pro-inflammatory genes was determined by qPCR. The total and phosphorylated protein levels were examined by Western blotting. The in vivo anti-inflammatory activities were evaluated by using mouse and zebrafish models. Results: PP7 reduced the production of NO and PGE2 and the protein and mRNA expressions of pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) and enzymes (inducible NO synthase [iNOS], cyclooxygenase-2 [COX-2], and Matrix metalloproteinase-9 [MMP-9]) in LPS-induced RAW264.7 cells by suppressing the NF-κB and MAPKs pathways. Notably, PP7 markedly inhibited xylene-induced ear edema and cotton pellet-induced granuloma formation in mice and suppressed LPS and CuSO4-induced inflammation and toxicity in zebrafish embryos. Conclusion: This study demonstrates that PP7 exerts strong anti-inflammatory activities in multiple in vitro and in vivo models and suggests that PP7 is a potential novel therapeutic agent for inflammatory diseases.


Author(s):  
Sana Khurshid ◽  
Sana Javaid Awan ◽  
Ateeqa Naz ◽  
Safdar Hayat Khan ◽  
Saira Fiaz

Medicinal plants have been used to treat diseases for centuries. One group of such plants is Ziziphus species belonging to Rhamnaceae family. The extracts from plants of this genus has been found beneficial for the treatment of cancer caused by high production of reactive oxygen species resulting from different oxidative stress mediated conditions. The mechanism of anticancer activity of two different species of this plant (Z.jujube and Z.mauritiana) have been discussed in this review. The constituents of this plant include the flavonoids, triterpenes, potassium, calcium, phosphorus, iron, zinc, copper and polysaccharides such as reducing and non-reducing sugars. The underlying mechanisms of both species include the (Tumor protein P53) P53, (signal transducer and activator of transcription) STAT, (Matrix metalloproteinases) MMPs, (clustered regularly interspaced short palindromic repeats) CRISPR and flavonoids and triterpenic acid mechanisms. The effects of the extract on different cells lines in both in vitro and in vivo models have been studied by observing the induction of apoptosis and reduction in angiogenesis leading to reduction in progression and proliferation of cancer cell lines. The biological properties of Ziziphus include the anti-inflammatory, antioxidant, anticancer and hepato-protective characteristics.


2020 ◽  
Author(s):  
Patrick Kratschmer ◽  
Edgar Buhl ◽  
Ko-Fan Chen ◽  
Simon Lowe ◽  
Dimitri M. Kullmann ◽  
...  

ABSTRACTBackgroundGenetic and in vitro studies have linked a heterozygous gain-of-function mutation (D434G) in the hSlo1 BK (Big potassium) channel to paroxysmal dyskinesia. However, support for this linkage from in vivo models has been lacking.ObjectivesWe aimed to re-create the equivalent mutation to hSlo1 D434G in the fruit fly, Drosophila, and examine how this mutation altered movement and action potential waveforms.MethodsWe generated a knock-in Drosophila model of hSlo1 D434G. We used video-tracking and infra-red beam-break systems to test whether locomotion was altered in this model, and patch-clamp electrophysiology to determine how the mutation affected action potential waveforms.ResultsWe identified profound motor dysfunction and sporadic leg twitches, as well as a reduced width and an enhancement of the afterhyperpolarization phase of action potentials, in the model background.ConclusionOur results support a conserved relationship between enhanced BK channel function and disrupted motor control across distantly related species.


2021 ◽  
Author(s):  
◽  
Tanisha Vithal

<p>Alzheimer’s disease (AD) is a neurodegenerative disease that is responsible for 50-80% of dementia cases and is characterised by lack of visuospatial perception, impairment of language and memory. One of the main physiological attributions towards this disease is the accumulation of large insoluble deposits of amyloid beta, a toxic peptide, which results in the generation of amyloid plaques found in between neurons in the brain. Currently no therapeutic treatments are available. Clusterin (CLU) is an apolipoprotein that when defective is the second highest genetic risk factor for AD. It has been strongly debated whether CLU counteracts or promotes AD pathology. With the roles of CLU including but not limited to acting as a chaperone for cholesterol transport and aiding autophagy functionality in cancer models, this thesis investigates these two specific functionalities by overexpressing CLU in an in vitro SH-SY5Y and in an in vivo AD model of Drosophila melanogaster (fruit fly). Conclusions from this study reveal that within D. melanogaster, CLU reduced Aβ42 levels and increased cholesterol effect through the blood brain barrier. Additionally, in human cells, CLU ameliorated the defective flux in autophagy. This thesis sheds light into how CLU plays a protective role within an Alzheimer’s disease mammalian system.</p>


2019 ◽  
Vol 2 (4) ◽  
pp. 83-98 ◽  
Author(s):  
André De Lima Mota ◽  
Bruna Vitorasso Jardim-Perassi ◽  
Tialfi Bergamin De Castro ◽  
Jucimara Colombo ◽  
Nathália Martins Sonehara ◽  
...  

Breast cancer is the most common cancer among women and has a high mortality rate. Adverse conditions in the tumor microenvironment, such as hypoxia and acidosis, may exert selective pressure on the tumor, selecting subpopulations of tumor cells with advantages for survival in this environment. In this context, therapeutic agents that can modify these conditions, and consequently the intratumoral heterogeneity need to be explored. Melatonin, in addition to its physiological effects, exhibits important anti-tumor actions which may associate with modification of hypoxia and Warburg effect. In this study, we have evaluated the action of melatonin on tumor growth and tumor metabolism by different markers of hypoxia and glucose metabolism (HIF-1α, glucose transporters GLUT1 and GLUT3 and carbonic anhydrases CA-IX and CA-XII) in triple negative breast cancer model. In an in vitro study, gene and protein expressions of these markers were evaluated by quantitative real-time PCR and immunocytochemistry, respectively. The effects of melatonin were also tested in a MDA-MB-231 xenograft animal model. Results showed that melatonin treatment reduced the viability of MDA-MB-231 cells and tumor growth in Balb/c nude mice (p <0.05). The treatment significantly decreased HIF-1α gene and protein expression concomitantly with the expression of GLUT1, GLUT3, CA-IX and CA-XII (p <0.05). These results strongly suggest that melatonin down-regulates HIF-1α expression and regulates glucose metabolism in breast tumor cells, therefore, controlling hypoxia and tumor progression. 


2019 ◽  
Vol 26 (16) ◽  
pp. 2974-2986 ◽  
Author(s):  
Kwang-sun Kim

Vectors are living organisms that transmit infectious diseases from an infected animal to humans or another animal. Biological vectors such as mosquitoes, ticks, and sand flies carry pathogens that multiply within their bodies prior to delivery to a new host. The increased prevalence of Vector-Borne Diseases (VBDs) such as Aedes-borne dengue, Chikungunya (CHIKV), Zika (ZIKV), malaria, Tick-Borne Disease (TBD), and scrub typhus has a huge impact on the health of both humans and livestock worldwide. In particular, zoonotic diseases transmitted by mosquitoes and ticks place a considerable burden on public health. Vaccines, drugs, and vector control methods have been developed to prevent and treat VBDs and have prevented millions of deaths. However, development of such strategies is falling behind the rapid emergence of VBDs. Therefore, a comprehensive approach to fighting VBDs must be considered immediately. In this review, I focus on the challenges posed by emerging outbreaks of VBDs and discuss available drugs and vaccines designed to overcome this burden. Research into promising drugs needs to be upgraded and fast-tracked, and novel drugs or vaccines being tested in in vitro and in vivo models need to be moved into human clinical trials. Active preventive tactics, as well as new and upgraded diagnostics, surveillance, treatments, and vaccination strategies, need to be monitored constantly if we are to manage VBDs of medical importance.


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