Why haven’t we cured arthritis? - Kaitlyn Sadtler and Heather J. Faust

翻译人员: Carol Wang 校对人员: Jiasi Hao

While regaling you with daring stories from her youth,

当奶奶讲起年轻时的大胆经历时，

it might be hard to believe your grandmother used to be a trapeze artist.

你可能很难相信 她曾是一位飞人艺术家。

However, the bad backs, elbow pain, and creaky knees so common in older people

然而，老年人常见的背痛、肘痛 和膝盖吱吱作响的毛病

is more than just “old age."

不仅仅只是“老年病”，

In fact, the source of this stiffness plagues many young people as well.

事实上，这种僵硬的根源 也困扰着许多年轻人。

The culprit is arthritis:

其罪魁祸首就是关节炎：

a condition that causes inflammation and pain in the joints

仅在美国，超过九千万人

of over 90 million people in the U.S. alone.

遭受其导致的关节发炎和疼痛。

But are stiff, creaky joints really inevitable?

僵硬而老旧的关节毛病 真的无法避免吗？

What makes arthritis so pervasive,

什么原因使关节炎如此普遍，

and why haven’t we found a cure for this widespread condition?

为什么我们还没找到 这种常见病的治愈方法呢？

The first hurdle is that arthritis is actually a spectrum

第一个难题是，关节炎

其实是 100 多种不同关节病的总称，

of over 100 different arthritic conditions.

All these conditions share symptoms of joint pain and inflammation,

它们都有关节疼痛和发炎的症状，

but the origin and severity of those symptoms vary widely.

但是这些症状的起源 和严重程度差异很大。

Even the most common type, osteoarthritis,

即使要避免最常见的骨关节炎，

is trickier to prevent than one might think.

也比人们想象的难得多。

It’s a general misconception that arthritis is confined to old age.

人们普遍误以为关节炎只是老年病，

The origins of osteoarthritis can often be traced to a patient’s early life,

骨关节炎的病根，通常可追溯到

患者早些年看似普通的关节损伤。

from any seemingly ordinary joint injury.

Following impact, immune cells rush in to help clean and repair the damaged site

关节遭受冲击后，免疫细胞涌入 以帮助清理和修复受损部位，

and begin pumping out enzymes,

并释放包括基质金属蛋白酶

including matrix metalloproteinases and aggrecanases.

和聚集蛋白聚糖酶在内的酶。

These enzymes clear out the damaged tissue and contribute to inflammation.

这些酶清除受损组织， 并引起发炎症状。

But while this rapid swelling helps protect the joint during recovery,

但是，尽管这种迅速的肿胀 有助于在恢复过程中保护关节，

inadequately healed tissue can cause these immune cells to overstay their welcome.

但是，愈合不充分的组织 可能会导致免疫细胞滞留。

The continuing flood of enzymes starts to degrade the cartilage,

持续的酶代谢使软骨退化、

weakening the joint and leading to arthritis later on.

削弱关节， 并后来发展为关节炎。

Not all forms of arthritis can simply be traced to an old sports injury.

并非所有形式的关节炎 都能简单追溯到旧运动损伤，

Take rheumatoid arthritis, which affects 1.3 million U.S. adults.

以类风湿关节炎为例， 这种疾病影响到 130 万美国成年人，

This condition is actually an autoimmune disease

这种情况实际是自身免疫性疾病，

in which autoantibodies target natively produced proteins,

自身抗体靶向正常产生的蛋白质，

some of which are secreted by cartilage cells.

有些蛋白质是软骨细胞分泌的。

We still don’t know what causes this behavior,

我们仍然不知道导致这种行为的原因，

but the result is that the body treats joint tissue like a foreign invader.

但结果是，人体错把关节组织 当成外来入侵者一样对待。

Immune cells infiltrate the joint despite there being no tissue damage to repair.

免疫细胞涌入关节， 尽管没有组织损伤需要修复。

This response leads to chronic inflammation,

这种反应导致慢性炎症，

which destroys bone and cartilage.

破坏骨骼和软骨。

Yet another condition, spondyloarthritis,

另一种疾病脊椎关节炎，

has similarities to both of the conditions we’ve covered.

与我们刚才提到的两种情况类似。

Patients experience continuous inflammation in the joints

即使初期没有任何伤害的情况下，

and at the sites where ligaments and tendons attach to bones,

患者的关节、韧带 以及肌腱附着的骨骼部位

even without any initial injury.

也会持续发炎，

This leads to the flood of enzymes and degradation seen in osteoarthritis,

也出现骨关节炎中 产生大量酶和削弱关节的现象，

but is driven by different inflammatory proteins called cytokines.

但由不同的炎症蛋白引起， 这种蛋白称为细胞因子。

As the enzymes eat away at cartilage,

随着酶不断吞噬软骨，

the body attempts to stabilize smaller joints by fusing them together.

人体试图将较小关节 衔接起来以保持稳定。

This process sometimes leads to outgrowths called bone spurs,

这一过程有时会导致骨刺的生长，

which also cause intense stiffness and joint pain.

也会引起严重僵硬和关节痛。

With so many factors causing arthritis,

有许多导致关节炎的因素，

our current treatments are tailored to tackle specific symptoms

我们目前的治疗方法 只是专门针对特定症状，

rather than underlying causes.

而非潜在的病因。

These range from promising MACI techniques,

这些包括有前景的 MACI 技术 （自体软骨细胞移植技术），

which harvest cells from small pieces of cartilage to grow replacement tissue.

该技术可从软骨切片中 提取细胞以培养移植组织，

To a technique called microfracture,

还有一种微骨折的技术，

where surgeons create small holes in the bone,

在这种技术中， 外科医生会在骨骼上打小孔，

allowing bone marrow stem cells to leak out and form new cartilage.

从而使骨髓干细胞流出 并生成新的软骨。

As a last resort,

作为最后的选择，

people with withered cartilage can even undergo full joint replacements.

软骨萎缩的人 甚至可以进行全关节置换。

But outside these drastic measures,

但除了这些激进的治疗措施外，

the underlying drivers of autoimmune arthritis

自身免疫性关节炎的潜在病因

still present a unique treatment challenge.

仍然提出了独特的治疗挑战。

Scientists are making progress with therapies that block TNF-alpha,

科学家在阻断 TNF-α 疗法上 正取得研究进展，

one of the primary proteins causing inflammation in rheumatoid arthritis.

TNF-α 是导致类风湿关节炎 发炎的主要蛋白质之一。

But even this approach only treats the symptoms of the condition, not the cause.

但是，即使这种方法 也只能治疗症状，而非病因。

In the meantime, some of our best defenses against arthritis are lifestyle choices:

同时，对关节炎的最佳防治方法 是生活方式的选择：

maintaining a healthy weight to take pressure off joints,

保持健康的体重以减轻关节压力，

low-impact exercises like yoga or cycling, and avoiding smoking.

选择低影响的运动 如瑜伽或骑自行车，并避免吸烟。

These arthritis-fighting behaviors can help us lead longer lives

面对种类繁多的关节炎病，

在我们继续研究治愈方法 和治疗方案的同时，

as we continue to research cures and treatments

for the huge diversity of arthritic conditions.

这些抗关节炎行为 可以帮助我们延长寿命。