Combination of tauroursodeoxycholic acid, co-enzyme Q10 and creatine demonstrates additive neuroprotective effects in in-vitro models of Parkinson's disease

Abstract

This study aimed to evaluate different combinations of three dietary supplements for potential additive or synergistic effects in an in vitro Parkinson's Disease model. The complex and diverse processes leading to neurodegeneration in each patient with a neurodegenerative disorder cannot be effectively addressed by a single medication. Instead, various combinations of potentially neuroprotective agents targeting different disease mechanisms simultaneously may show improved additive or synergistic efficacy in slowing the disease progression and allowing the agents to be utilized at lower doses to minimize side effects. We evaluated four possible combinations of the three selected supplements: tauroursodeoxycholic acid (TUDCA), co-enzyme Q10 (CoQ10), and creatine, chosen for their effects on different targets that had previously shown neuroprotective effects in preclinical models. We evaluated the following combinations: (1) TUDCA+CoQ10, (2) TUDCA+Creatine, (3) CoQ10 + Creatine, and (4) TUDCA+CoQ10 + Creatine. We used induced pluripotent stem cell (iPSC) derived human dopaminergic neurons from a patient with Parkinson's disease and healthy control, as well as microglial cells, to evaluate for an additive or synergistic effect of these combinations on neurodegeneration and neuroinflammation. We used neurofilament heavy chain, tubulin filament, and proinflammatory cytokines as metrics. We have identified a triple combination of these supplements that showed an additive protective effect across all these endpoints. Indeed, the agents in that combination could address the majority of the known pathways leading to neurodegeneration, such as accumulation of misfolded α-synuclein, mitochondrial dysfunction, reactive oxygen species, and neuroinflammation. We demonstrated that the combination of TUDCA, CoQ10, and creatine exerts an additive effect in in vitro models of a neurodegenerative disease, surpassing the efficacy of each compound individually. This combination shows strong potential as a candidate for further preclinical confirmatory studies and clinical trials as a neuroprotective treatment for patients with, or at risk for, Parkinson's disease.

Keywords: Parkinson's disease; combination therapy; iPSC cells; in vitro model; neuroprotection.

Figure 1

Multiple processes leading to neurodegeneration in PD include: misfolding of proteins that fail to be cleared from the brain, which in turn stimulates neuroimmune responses; calcium excitotoxicity, affecting mitochondria and resulting in energy depletion, leading to neurodegeneration; iron accumulation that leads to activation of microglia and further neuroinflammation, causing oxidative stress, formation of reactive oxygen species (ROS); and mitochondrial dysfunction, and neuroinflammation all of which ultimately contributes to neurodegeneration. Supplements in parenthesis are thought to inhibit the corresponding process.

Figure 2

Effects of compound treatment on neural network density of idiopathic PD cell line. (A) Neurons are stained for neurofilament heavy chain (NFH) to visualize the neurite network. (B) Neurons are stained for βIII-tubulin to visualize the neurite network. (A,B) Bars represent the mean surface area of the stained neurite network per well, normalized against the mean area of the control (dimethyl sulfoxide [DMSO] only) wells. Values above 1 after compound treatment indicate an increase in neurite density compared to control. Error bars represent standard deviation. *p < 0.05; **p < 0.001.

Figure 3

Effects of compound treatment on neural network density of healthy control cell line. Neurons are stained for the neuronal marker MAP2 to visualize the neurite network. Bars represent the mean surface area of the stained neurite network per well, normalized against the mean area of the control (dimethyl sulfoxide [DMSO] only) wells. Error bars represent standard deviation. *p < 0.05.

Figure 4

Effect of the experimental conditions on the secretion of proinflammatory cytokines in iPSC-derived microglial cultures. Following treatment, the levels of proinflammatory cytokines interleukin 6 (IL-6; panel A) and tumor necrosis factor-α (TNF-α; panel B) in the supernatants of induced pluripotent stem cell (iPSC)-derived microglia-like cells (iMGLs) was analyzed. The measures are expressed in pg./ml. *p < 0.05; **p < 0.001.